Themanda-s03e04-720p-multi-pldub.mkv -

Specifically, refers to Season 3, Episode 4, titled "Chapter 20: The Foundling." The rest of the filename gives away the technical details: 720p : The video resolution (Standard High Definition).

: Short for "Polish Dubbing," meaning it includes a Polish voice-over. themanda-s03e04-720p-multi-pldub.mkv

: Likely contains multiple audio tracks (different languages). Specifically, refers to Season 3, Episode 4, titled