let's pretend you need a serial number for windows xp pro.

in the search bar type in just like this - "Windows XP Professional" 94FBR

the key is the 94FBR code.. it was included with many MS Office registration codes so this will help you dramatically reduce the amount of 'fake' porn sites that trick you.

or if you want to find the serial for winzip 8.1 - "Winzip 8.1" 94FBR

just try it out, it's very quick and it works nicely..

kredit to mysahabat