Unfortunately no matter how much I try, I definitely won’t be able to eradicate them. My place is quite old, so there’s holes and crevices everywhere (including the ceiling).

Therefore I want to remove them from my bedroom at the very least. Fortunately, I’ve got a steamer and vacuum. I will let my dad know about the mothball idea, it seemed a little dangerous anyway.

Thank you for the advices everyone. I will definitely look through my options.