That's ok, "что" is used often enough. In compound sentences you can replace any "который" with "что", and vice versa, and there will be no mistake. If of cource these word are used as a conjunction. And there must be a comma before "что", as it is a compound sentence. — Тот совет, что (который) он мне дал, оказался бесполезным. — Компьютер, что стоит на столе, подключен к инетернету.

You're right, "который" is more common in this sense! "Что" is correct and is used but less often so it *might* stand out a little. it can add some diversity to your speech as well. P.s. We never shorten it to Чё when it's used in this sense ;)

I would say "которые". Our pop music seems to make our language difficult ro understand.

We have in russian two synonyms "те, что" and "которые". In this phrase "те," is omited for peculiar expression and colloquial genre of russian language

Agree with Moscal. It's a song. And in a song you need to choose words that are suitable with music. In our case - you cant use "который", besause u wont have possibility to sing it (too long). So "которые" was substituted with "что".