I create this smart rule to automatically add tags based on the name of the index file. But I have no idea why it just doesn’t work. I tried to empty the group and reestablish the index, but it still doesn’t work.
There might be a problem with assume Chinese characters, perhaps @meowky knows more about that.
Aside: a more detailed description of what you’re trying to do, what happens and what doesn’t happen, including summer file names, might be helpful. For example, what is “the index file” and what’s “the group”? Did you test your regular expression with regex101.com or similar tool?