how i can search players in the forum?

I don't exactly get you by searching players but you can go to community and select contacts and add them as a contact.

http://forum.toribash.com/member.php?username=

A more effective way imo is using google to its best extent by searching something along the lines of:
site:forum.toribash.com user cocacobra

If you type that into google it will show a bunch of threads I've been in and then you can find my post click on my name and view profile etc. Works well for other things like finding old threads.