You phone and computer will be checked thoroughly using automated tools. If they didn't find any sensitive keyword, you'll be fined and recorded in the system. If they find something, a detention for at least 3 days or ... forever.
That's the standard procedure. But polices in developed areas usually treat them like antragsdelikte(no trial without a complaint).
I guess by "Everybody I know who grew up in China" you mean those elites who speaks English and have already bypassed restrictions to talk to you online or travels to other countries. There's some selection bias here.