Search Button Query

I share my PC with my Son and Daughter.What do I have to do,to stop my children,from finding my pictures,videos,docs etc when they use their search facility on their desktop. For example,my daughter was searching for a video of hers that she had downloaded,but her search results showed videos of mine which included part of the search name she used.
I would be very grateful if anybody can help me with this problem.

You can put it in a hidden partition.
For 7 and vista
http://www.vistax64.com/tutorials/155795-drive-hide-unhide.html

Create separate user account(s) for your children, then set user permissions on YOUR folders so that only your user can access them.