I recommend setting up a Meilisearch instance and configuring it for Chinese, or setting up Elasticsearch (ES) entirely. The built-in search functionality in Flarum is very limited when it comes to searching in Chinese.
There are also many online tutorials for configuring search in Flarum (
Edit: However, after looking at the Flarum ms search integration, it seems that the project's status is also questionable. It may not be in a state where it can be safely deployed to production.