Both Lexis and Westlaw have China-specific versions, which the UCLA Law Library does not subscribe to.
However, the US Lexis and Westlaw subscriptions include some basic Chinese law material:
Generally, the most useful tools for researching foreign law on Westlaw and Lexis are their Practical Law and Practical Guidance tools. These tools provide articles, Q&As, and other short, practical guides written by attorneys familiar with a country for attorneys who are unfamiliar with that country.
Both Practical Law and Practical Guidance include materials on Chinese law: