catfish (A versatile file searching tool)

Catfish is a frontend for different search engines
(daemons). The interface is intentionally lightweight and
simple, using only GTK+ 2.  You can configure it to your
needs by using several command line options.

Supported backends:

find, (s)locate, doodle, tracker, beagle, strigi and pinot

NOTE: for this to work the dependencies must be built
with python3 support (have a look at their READMEs)