Resolved iTunes Search function stopped working

No idea why.
Search is non functional. No results for song, artist - nothing.
Using Ver 7.6.0.29
Category is set to Artist.

 

I see there's a wealth of info on iTunes search function!

Well, strangely enough tonight it's working again.
And nothing has changed (no software adjustments on my part).
Go figure!

I won't mark this resolved as yet, since it's really not.
Still hoping someone will come up w/ an explanation.

 

I think I've found the answer - well, sort of.
The search function started working again after the computer was restarted.
This doesn't solve the problem, but at least explains what happened.

 

Addendum: It worked again after restarting iTunes.
Restarting the computer was not necessary.