Standard terms like "Polish video" yield millions of generic results. A hyper-specific string targeting a exact scenario (a public transit vehicle) lowers competition for webmasters trying to rank on the first page of search results.
If you are looking for information on this topic, here is the context of what those terms generally signify in the Polish internet landscape: MPK (Miejskie Przedsiębiorstwo Komunikacyjne): m3zatkamilfobciagakutasakierowcympkpolish exclusive