No, they won't. Unless they have specific reasons (such as a tip-off) that you are trying to smuggle illegal materials (porn, propaganda etc for distribution in China), they will not care about this. They primarily focus is on security-relevant issues and items for which you need to pay duty.

I never in my life had anyone check documents, laptop, cellphone or laptop contents in a routine check, anywhere in the world.

Of course, if you make trouble at the border and they take you in, they might check everything they can.