At first I wasn't sure what you were talking about, I rarely use the File:Search Files command.
So I thought I would check for myself.
You're right, the searching doesn't find what you imagine it would, because you are imagining it is searching "within" the files.
What it actually is doing is searching for "files" not "text".
Clearly what is needed is a rename of the command to "File:Find Files"
"Search" gives the impression of looking **into **the files, not looking **for **the files. IMO.