(scams in China) how are they different from nigerian scams?

Nigerian scams seem to start off with an email.

Chinese scams, ie tea house, taxi, etc are done in real person.

Just by looking at the content of the spam/scam emails, the ones from Nigeria often uses the "please help us" approach - ie. the type of scam you linked from Wikipedia. The ones from China mostly uses the "buy cheap" approach - ie. cheap drugs/watches/etc. Thus, the ones from Nigeria mostly end up with identity theft and money loss, whereas the ones from China generally results in just money loss.

the scams in China target Chinese people including Overseas Chinese using Chinese language.

The Nigerian scams target people that understand English located globally using English language (Nigeria was ruled by Britain)

the difference is that they are in a different country
the same scams are run all over the world, some are more common in some areas than others but theyre pretty much the same