BMNM

OQ is the best thing to happen to WoW. Thank you for making it.

It just needs one thing:
A way to narrow your search, from the search field.

For example:
I want to find a Normal SoO at Sha of Pride, without having to sort through any of the Flexes nor those that are at Shamans:

soo +sha -shamans -flex

I want to find a Flex that isn't Flex 1 or 2 because I just did them.

flex -1 -2
or
flex -"flex 1" -"flex 2"

Just like Google does.
This way, you don't have the impossible task of coming up with every possible thing to filter for. Just let people filter for whatever they want, with an instrument that can cut the fat with precision.