To see if it's what you want, open a terminal
and type gnome-search tool
It will search for files by name or type, accepts wildcards ( i.e., "*" ) and can search for files containing specified text. So you could search for all *.txt files that contain the word "Mint" for example.
It doesn't have an entry in the menu but you could put it in there yourself.
You can also create a desktop launcher for it.
You can even create a right click option for use in Nautilus: viewtopic.php?f=60&t=27081#p157068