Any way to make a system-wide search??

Searching inside Android seems rather rudimentary. I want to be able to find any file on mine. Not just music and apps and stuff, but, say, a .xml file that turns out to be inside /system/etc. Come to that, a search facility that could find and take me to a word/number inside that file, too.

A pop-up that will allow a search even inside such limited apps as ES File Explorer Editor that have no built-in search function. It need not maintain an index, even a brute-force search would do for most such search jobs. Maybe a wrapper (that opens an input box under the keyboard?) around the Linux 'find' command?

Is there anything that will do all/most of this?

Bump

Or is this such a tired question that it's ignored? I can't believe that it's impossible on a rooted device.