Relic Locker Search Function not accessible?

I see an option to highlight items with a search but can't figure out how to access it to type something in.

There is a little check box which I can select by using Up & R3 but I can't tell what that does, if anything. There is also a little square with what looks like an hourglass symbol I can't tell what that means either.

Is this bugged or am I being dumb?