I will answer your question with a question: What do you want to achieve with what you wrote? Do you just want to convey an idea, or do you want to write the way a native English speaker would write? If you want to be understood, your version is fine. The 'corrected' version is OK, but if anything, less natural than yours. If you want it to be more natural though, you probably need to reword it. What sort of 'mysteries'? How are you attracted to them? Do you feel the need to go to them? 'Attractive' is different again. It does not mean 'that attract' - it actually just means 'are pretty'.

"China is full of mysteries that really attract" is not natural and I would argue that it isn't correct. "China is full of mysteries that really attract me." <-- This is the best option in your list. You could also say: "China is full of mysteries that really interest me." "Attractive" is mostly commonly used to describe someone or something that is physically appealing, so the last sentence isn't incorrect, but it's a little unnatural. I hope that helps!