When I'm using the regular Start Menu, Search only gives me apps. When I am using the App Grid, I also get files, settings and characters.
I am leaning toward the Grid. The only drawback is you can't create Chrome App shortcuts on the desktop, only on the taskbar. Tried via chrome://apps but it doesn't work.
If using Cinnamon or if using XFCE > whiskermenu, you can get files and other stuff in the app menu search.
I'm not sure why Gnome is as it is... Gnome essentially banned having Desktop Icons.
Zorin OS includes an extension to get them back.
You might try using the most recent Arc Menu gnome extension on Core instead of the Zorin Menu and see if it allows for a greater search range.
I just realized you can get to the "good" search by clicking the Workspace button.