Yes, they will return your original documents. You will get your original documents . Once it verified your documents completely then it will return. They return your original documents after 5 to 6 months. Your Migration Certificate, TC and character certificate  will be submitted till 4 year of b.tech.
After that it will be given by College . So go through Information carefully. You can ask about this time to time to the college.  You will definitely get back your documents.

Hello dear aspirant

It all depends on college,  some of the colleges do keep your documents with them and the other colleges may give it back to you,  it is not an established rule.
You may request the college to return it to you.

Hope I am clear

Hello Jayram,

If you submit your original documents to a B.Tech College, Depending on the college they do return most of the original documents. The transfer certificate is not returned immediately but after the completion of the course, you get a new one from the college, for M.Tech.

Hope this helps.