Remove Traces Of Songs Downloaded From Computer?

i use a Internet to mp3 convertor to download songs on my pc.i use google chrome. the thing is, my dad also uses the computer im using and i knoe he will get pissed if he found out i was downloading music. i deleted them from downloadsin google and downloads folder. i deleted them form recycling bin.

however when i go to my computer and go to local disc c and type in song name, i see a remain of the song.i cant delete because it says the file cant be opened im afraid my dad will see these remains. how can i delete remains of the songs.