Don't put .bsp in or it probably won't bring up any results. We blocked the search *.bsp to avoid any flooding, so if you want to search for something just put in the name without the extension.
!find will bring up any matches that have that term in it.
Example: !find shazam brings up all the shazam maps
!efind is for the exact search term, so if you know the exact map name then you can use !efind and not get spammed with matching results.
!efind shazam will only bring up shazam.bsp and none of the other shazam maps