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Sorry Nurkasih, I do not fully understand the lingo.
But I can see you already have the keyboard protector/cover. So it is your touch pad that is yellowing. Well, the MacBook (few years) I am using is fully cream coloured already.

There are 2 types of nail polish remover. Acetone and Non-Acetone. The normal type is acetone which is a big no no to clean your laptop. Look for the non-acetone type. Our IT staff has used it.