certain things work in CentOS but not in Debian
 

i've been using debian for over year and recently i installed centos.
in debian doesn't work FN + shortcut for brightness neither cheese(extremely lagging).
to my surprise, it works in centos.
my question is, if it works in centos how can i get this working in debian ?
i have no idea what has to be done in order to acheive that.
few months ago i was trying to figure it out(found few manuals how to do that but none of them worked for me) but i gave up.
btw i am using laptop toshiba optimus p750.

I have no way of testing this, but Debian is aggressively free and certain proprietary drivers that make it into other distros don't make it into Debian by default.

You may be able to find the drivers you need in Debian's non-free repos:

http://www.debian.org/distrib/packages