Ms.Marta, you can have a try to apply for Chinese F visa in Spain, if you are refused, then you have to return to Poland to apply for it. The visa regulations vary according to nationality of applicants. In principal, you need a Spain visa or residence permit which entitles you live in Spain for a long time if you want to get Chinese visa in Spain. However, you don't have neither of them, just have a try, good luck!