Mr. Kalaiselvan has given valuable advice. Kindly follow it.
Did the company ask to submit certificates in writing?
The original educational certificates are result of many years of education, are personal property of the employee and employer can not have any lien on it.
There are court judgments declaring such tactics of the employer as illegal, unlawful………….e.g;
Dr.S.Rajesh vs The State Of Tamil Nadu
indiankanoon.org/doc/1028571
Record (audio/visual) the transactions while the demand for monies for returning the original certificates is being made and keep some witness.
The Bond/service agreement has to be in lieu of some extra ordinary favor by company, expense incurred by it on specialized training that added to extra ordinary skills, qualification…………
If no such expense is incurred by company the claim on Bond/liquidated damages may not stand the test of law…………………………………The courts of law would look into reasonableness of the matter and reasonable amounts if any…………………
The agreements are crafted and original certificates are collected to exert pressure and many of the cases employers may not resort to legal approach.
You should approach your labor consultant/service lawyer with copies of all of your docs, including but not limited to job advertisement, job application, offer letter, selection letter, offer letter, appointment letter, bond, communication asking you to submit original educational certificates, receipt issued by company for certificates………………..spend quality time with your lawyer, give inputs, and understand the merits and proceed under expert advice of your lawyer.
In the meantime go thru the attachments.
Another similar query is posted at:
https://www.lawyersclubindia.com/forum/Advice-on-termination-90640.asp#.UmFN8tKAqWN