This is an incredibly powerful full-text search software – specifically, not just full-text search, because it can also find all sorts of unexpected things. The name of this software is Beagle; it’s a project under Gnome, and its Chinese name is "Search and Index."
By default, this software isn't installed in Ubuntu, but as a project under Gnome, it has excellent compatibility and synergy with Gnome. If you have a lot of clutter on your computer and need to search for data in various situations (not just simple files), I think you’ll definitely need it. Let’s first take a look at how I use it!