xfdesktop - The xfdesktop application manages the desktop backdrop.
Meta Search - Search your Desktop, Google Drive, Dropbox, Gmail, Evernote.
cryo - A visual file manager
Google Cloud Search - Search across all your company's content in G Suite.
GNOME Commander - GNOME Commander is a "two-pane" graphical file manager for the GNOME desktop environment.
Vaultedge - Access all your documents in one place.