It is not a question type search, it is strictly a keyword search and all the words must be a minimum of 4 characters; in addition, words like THAT and THIS are considered common and are ignored. It also does not have the facility to handle quoted phrases, which I personally would like. Sorry, that is a limitation of the version of forum software currently in use.
I did find this
THREAD
But to do so I took your quoted search to bing and added w7forums after it.
It is recommended you
run a chkdsk on your drive.
From an administrator command prompt do ...
Chkdsk x: /F/R (where x is your drive letter)