hidden files still showing in finder?

I have a bunch of private files on my mac, pictures, word docs, etc.

and a lot of my friends would use my computer from time to time so i really can't leave them out in the open

anyway I hid the files through the terminal using this code

"chflags hidden ~/Desktop/pvt"

and at start i thought it worked since the file dissapeared from the desktop but when i searched for the file in the finder it still came up as if unhidden!

does the finder always show hidden files?

am I hidding them icorrectly?

also if someone knows a FREE app that works on the mac that would protect files with a password and would hide them from finder?

also to make matters worse when i search in finder no matter what i write the hidden files are the first thing to show for like a second

so lets say a hidden file is called "A" and i search "X" the hidden file "A" will be the first in the list for a second then the finder will show the files that actualy contain x