Translation:Matěj and František are good fathers.
I was told by a friend that "-ové" is the nominative plural ending for (at least many) one-syllable male animate nouns. Also works for muž, syn, Ital, Rus, Fin, pes, osel,...
Psové is quite unusual. Reminds me a famous poem by Jan Neruda that starts "Jak lvové bijem o mříže". Lvové - lions - is normally just lvi and psové is normally just psi.
masculine animate soft stem (paradigms muž and soudce), there is a competition of -i and -ové with various degree of preference