I searched Lexis-Nexis for past news articles mentioning Tan Cheng Bock. Ideally, I would have searched the Hansard as well, but I have no access to it. While he was involved in a wide range of issues, I do not have the time to list all of them, so here are the ones that I found more interesting. I excerpt the relevant articles below.

On NMPs:

Parliament “aye’ for Nominated MPs
Zuraidah Ibrahim
May 30, 1992
The Straits Times
PARLIAMENT yesterday voted in favour of having Nominated MPs for its current term after a spirited debate that saw dissenting voices from among both opposition and PAP ranks.
For the first time since 1979, the PAP lifted its party whip, enabling its MPs to according to their conscience.
Four of them argued against continuing the NMP scheme. But only one, Dr Tan Cheng Bock (Ayer Rajah), raised a hand and uttered “nay” when a voice vote was called at the end of the three-hour debate that had 21 MPs speaking up.
The others, Feedback Unit chief Ow Chin Hock, Dr Arthur Beng (Bedok GRC), and Mr Leong Horn Kee (Thomson GRC) appeared to have kept silent. The four opposition MPs voted against it.
[…]
Those against the scheme went back to principles, arguing that it went against the democratic axiom that the people’s representatives must be elected, with Dr Tan leading the discussion on this.

The Straits Times (Singapore)
Govt moves to up number of NMPs to 9
June 6, 1997
Tan Hsueh Yun
NEW legislation will be introduced to increase the number of Nominated Members of Parliament from six to nine.
Leaders of key functional groups in business and industry, the professions and the labour movement will also be asked to nominate their members as Nominated MPs.
Leader of the House Wong Kan Seng announced this in Parliament yesterday when he moved a motion to resolve that there will be Nominated MPs during this term of Parliament.
The party whip was lifted and the motion was passed with two dissenting votes -from Dr Tan Cheng Bock (Ayer Rajah) and Mr Low Thia Khiang (Hougang). Non-Constituency MP J. B. Jeyaretnam abstained from voting.

On Chee Soon Juan (several articles):

Dr Chee affair: SDP rapped in Parliament
April 14, 1993
House dismisses party’s claims that sacking was politically motivated PARLIAMENT yesterday rapped the Singapore Democratic Party for politicising the Chee Soon Juan affair.
It did so after a 4-1/2-hour debate that threw up new evidence against the former lecturer, who is the party’s assistant secretary- general.
It dismissed claims by the SDP that the National University of Singapore’s sacking of him was politically motivated.
This was, in effect, a turning of the tables on the opposition as the debate had begun on a motion tabled by NMP Chia Shi Teck calling for the “actual facts” about the dismissal to be made public, a move for which he was thanked by SDP chief Chiam See Tong.
But after the House heard revelation after revelation about Dr Chee’s conduct, Ayer Rajah MP Tan Cheng Bock moved to amend the original motion to one stating that Parliament “deplores the SDP’s action in politicising an internal NUS disciplinary matter and pressuring NUS to rescind its action against a dishonest staff member”.

“He was so captured by the tremendous response … he lost his sense of judgment and reality. He became a victim of his own psychological training when he started to tread on the fringe of megalomaniac behaviour.
His self-importance and delusions of greatness … made him to challenge authority, his immediate superiors, his university, his own party, his family’s attempts to stop him on embarking on his hunger strike and even has the audacity to urge the SDP to pressure the university.”
-Dr Tan Cheng Bock (Ayer Rajah), giving his assessment of Dr Chee’s behaviour since the Marine Parade by-election.

The Straits Times (Singapore)
Implications of Chee’s sponsored ticket to Williams
November 4, 1995
DR TAN Cheng Bock (Ayer Rajah) yesterday criticised Dr Chee Soon Juan for going to Williams College on a sponsored air ticket. The implication of travelling on a sponsored air ticket was that the sponsors hoped to get something in return, he said.
Referring to the ticket paid by a student association, Polis, at the college, he added that the “anti-Goh” group there had wanted Dr Chee to provide credibility and help strengthen its case.
“The person who accepts the ticket has an obligation to return something back out of gratitude,” he said, noting that at the college, Dr Chee had agreed with many things, though not all of the remarks, made by Mr Francis Seow, Dr Christopher Lingle, Mr William Safire and Dr George Crane.
He said the Singapore Democratic Party was either naive in failing to see the hidden agenda or its leadership was silly to accept the invitation. “It will discredit the SDP’s leadership because the SDP has positioned itself by allowing outsiders into the Singapore political arena, helping them interfere in our domestic politics,” he said.
He added that when MPs went abroad to attend international conferences and meetings, they often had to explain difficult issues such as detention without trial, human rights and press freedom.
“But we have never let ourselves to be used by foreigners for their own ends because this is our responsibility to the Singapore people who voted us in,” he said.

“Singaporeans must therefore judge wisely whether they want such leaders who are prepared to stand side-by-side with foreigners in a foreign land, condemning the government Singaporeans voted for in the last 30 years. Is this the proper and correct behaviour of true Singaporeans ?”
-Dr Tan Cheng Bock (Ayer Rajah).

(That last excerpt is part of a list of quotes on the Williams College invitation. Incidentally, Goh Chok Tong gave a speech at Williams College in 2010.)

On bond-breaking doctors:

The Straits Times (Singapore)
“Don’t strike off’ bond-breaking doctors
August 26, 1997
- MPs speak out strongly against proposal
SEVERAL MPs yesterday took issue with the proposal to penalise young doctors who break their five-year bonds with the Government by having them struck off the medical register.
Dr Tan Cheng Bock (Ayer Rajah), Dr Michael Lim (Cheng San GRC), Dr Toh See Kiat (Aljunied GRC) and NCMP J. B. Jeyaretnam all spoke strongly on this point during the second reading of the Medical Registration Bill, moved by Health Minister Yeo Cheow Tong.
The new law empowers the Medical Council to strike a doctor off the register if he leaves a government hospital before his five-year bond is up.
Dr Tan, a medical doctor, argued that bond-breaking had nothing to do with a doctor’s competence, as he might just dislike working in a particular hospital.

On Philip Yeo asking Chng Hee Kok to resign over the bond-breaking issue:

The Straits Times (Singapore)
What does the issue of bond-breaking have to do with recession?
March 10, 1998
Koh Buck Song
SURPRISINGLY, the pros and cons of shaming bond-breakers drew the most fireworks in the first half of yesterday’s opening day of the Budget debate.
The MPs who raised the issue most forcefully -Dr Tan Cheng Bock (Ayer Rajah) and Mr Chng Hee Kok (East Coast GRC) -did so mainly because they saw it as an insult and affront to them as representatives of the people.
Based on the two MPs’ account of a recent meeting between Mr Chng and Economic Development Board officials including chairman Philip Yeo, it would seem a remarkable action on Mr Yeo’s part to have asked Mr Chng to resign just because he did not agree with the “government policy” of naming scholars who break their bonds.
Dr Tan’s characteristically spirited defence of elected MPs pushed on, despite an unsuccessful intervention by Leader of the House Wong Kan Seng, asking him to stick to issues on the Budget.
The veteran MP cited three reasons for raising the issue: the need to nurture the creativity of young local talent, Mr Yeo’s unacceptable challenge to political leadership by asking for MPs’ resignations, and the right of MPs to hold alternative views.
Dr Tan drew laughter with his seemingly perfunctory effort to make his speech more relevant, by making just a passing reference to the Budget in a one-sentence compliment on Nominated MP Lee Tsao Yuan’s analysis. But even if he himself did not realise it, his “outburst”, to use Non-Constituency MP J. B. Jeyaretnam’s term, was not on a peripheral matter.

“Many of us in this House have spoken strongly against … government policies. And we were reprimanded by the ministers … taken to task even by the Prime Minister … Despite our differences in views, we were never asked by the Prime Minister to resign.”
-Dr Tan Cheng Bock (right) on Mr Yeo calling on Mr Chng to resign.

The Straits Times (Singapore)
EDB chief rapped for asking MP to quit over bond-breaking issue
March 10, 1998
Sandra Davie
In January, [Chng Hee Kok] said, he was invited to meet senior EDB and NCB officials and “the most senior gentleman at this meeting” accused him of sharing the bond-breakers’ values and told him he should resign from public office.
Mr Chng did not identify the official, but Ayer Rajah MP Tan Cheng Bock had no such scruples. Can Mr Chng confirm, he asked, that this man was the EDB chairman and that the latter then stormed out of the meeting? Mr Chng
did. Dr Tan spoke of his own “shock and disbelief” on learning of this from Mr Chng outside the House. He asked for more details.
Mr Chng said, among other things, that the EDB chief threatened to include Mr Chng’s name in its statement, and to say that the MP backed the three scholars.
The EDB chairman, he said, even suggested that the MP ought to have sent him that October speech for vetting beforehand.
The MP observed that in all his years in Parliament no minister or government official had ever asked to vet his speech, and he told Mr Yeo so, he said.
When he sat down, the Leader of the House, Home Affairs Minister Wong Kan Seng got up to say Members of the House should confine their debate to the Budget statement.
But the Speaker allowed Dr Tan to continue as two other MPs had already touched on the same issue of naming bond-breakers. Dr Tan said he could not allow this episode to pass without expressing his concern. MPs who spoke strongly against government policies had been taken to task before, he said.
“But we are still not embarrassed because we have spoken out honestly and frankly what we believe in, and also to let the Government know how the people at the ground feel. Despite our differences in views, we were never asked by the Prime Minister to resign.”
Holding up a copy of an article from the magazine Pioneers of Computing, Dr Tan said that in an interview there, Mr Yeo had spoken against the government policy of upgrading HDB flats.
Said Dr Tan: “In other words, he disagreed with this major government policy. No one asked him to resign. Yet he wants Chng Hee Kok to resign and other MPs to also resign!”
In another part of the article, he said, the EDB chairman spoke of the lack of creativity in Singapore leaders. Dr Tan accused Mr Yeo of paying “lip service” to creativity.
He said: “All that is well said, but you ask yourself how to be creative where the leader of the company has no room for differing views?”
This, he said, was a serious matter.
“I see this action as an affront to the office of the elected Members of this House, by a member of the Administrative Service.”
The EDB chief, he said, had even tried to summon MPs who opposed the EDB’s move to meet him to discuss the issue further.
“Has he the right to summon MPs for a meeting to answer to him why they disagree? Is he getting too big for his shoes?” asked Dr Tan.