KDE interface not fully displayed in Chinese (Traditional)

Hi, I find that many components of the interface of the Application Menu, Dolphin etc are not translated or I believe not displayed properly in Chinese (Traditional) but fallback to English. I have another laptop where the components are in Chinese. How can I identify the cause and get it solved? Thank you.

Locale - ArchWiki (My system is still using wrong language) suggests that the issue can be solved by deleting ~/.config/plasma-localerc. and it does solve the issue on my PC.

Many translations are incomplete. Anyone can participate. Translations are usually done by volunteers. More info here.

I think it is not about the translation work. Like I mentioned earlier, the interface is relatively better (refer to the screenshots below) on my other laptop with the same version of Manjaro.

Oh, I see now.