You are not doing anything wrong. That's what usually happens when you search for videos, it seems to give you all the files that contains each of the keywords you typed.

What I do to avoid being flooded with unrelated files is to type the artist's name instead and later on locate for the title I'm looking for

OR to get more specific results choose the type of file from "select type" (e.g. videos), in the title box type the title AND artist's name if you are looking for music videos