Hey Shanu, 

You can try this link for downloading the previous years papers.

http://sscbs.du.ac.in/index.php/contact-us/previous-year-question-papers-bms-bba-fia-entrance-exam

You can also get the previous years papers in DU north campus book store. All these are provided in the bungalow road, the most common one is Datta book store. You can get all the previous years papers in a form of booklet of whichever subject/entrance you want.

Hope this helps!

Good luck!