First of all, the International Patent Organization (WIPO) is a global patent organization, and its website provides global patent search services. China's patent information can be retrieved through WIPO's website.
Secondly, China National Intellectual Property Administration of China (CNIPA) also provides patent search service and discloses China's patent information to the world. Through CNIPA's website, you can search the patent information of China.
In addition, there are some third-party patent retrieval platforms, such as De Winter Innovation and PatSnap. The website also provides global patent search service, including patent information in China.
It should be noted that different patent retrieval platforms may provide different patent information, and some platforms may need to pay for more detailed information.