Are you referring to traditional chinese therapies, or new age ones? Most of the traditional therapies have seen more testing that a good number of western medical approaches to problems.
Regardless, the primary goal of practical medicine is to treat problems, and not to have a consistent or complete theory of treatment. If the goose is laying golden eggs, there's really no need to mess with it.
Some double blind studies appear to indicate that magnets are effective, but obviously the world is full of snake oil salesmen, and I don't have the time or inclination to research this a whole lot more.