Just started muon if i try a program with the search line "find" it finds by creating the list of all the files with the written features, but after installation almost always if i look for another program or even the same finds no more nothing and does not create any listings.
Muon is no longer maintained, please switch no a supported alternative like https://apps.kde.org/discover/ or the package manager native no your system. Sorry for the inconvenience.