This phrase is asking about your parents' occupations or jobs.
Here's a breakdown:
* Que: What (interrogative word)
* cosas: things, matters
* hacen: do, make
* tus: your
* padres: parents
You could also translate it as "What kind of things do your parents do?" which emphasizes the activities they engage in.
It's a casual question and can be used in various contexts, such as when getting to know someone or making conversation.