There are 3 books in the The Red Princess Mysteries series. The newest book is Dragon Bones which came out in 2003.

1
Flower Net

Flower Net
In the depths of a Beijing winter, during the waning days of Deng Xiaoping's reign, the U.S. ambassador's son is found dead - his body entombed in a frozen lake. Almost simultaneously, American officials find a ship adrift in the storm-churned waters off Southern California. No one is surprised to…
When you buy books, we may earn a commission that helps keep our lights on (or join the rebellion as a member).

2
The Interior

The Interior
Chinese police detective Liu Hulan and attorney David Stark journey deep into China when Hulan goes undercover in the factory of an American corporation