How to type CJK characters in collabora offile (package)?

I installed collabora office (CODE) to use nextcloud office by services.collabora-online.enable, it install collabora online from nixpkgs.
However I cannot type any CJK characters inside the nextcloud office.
When I type or paste those CJK characters in it, it just did nothing, not even scrambled characters.
Are there some settings that I need to configure in the nixos module?

I can type / paste those characters in the nextcloud office when official CODE docker images is used. But docker images is slow.

How did you install nextcloud office? Which commands are you running to start it?