Support for CJK language

I am trying it since last 2 days. I tried downloading CJK font from google font, tried dynamic font but in-game tmpro still shows me white rectangle. Just for example this is word 先月の販売. In google font I can see the same word perfectly but why not in textmeshpro, even if I use the same font?
Can anyone tell me what I am missing?

Edit: It seems like it is working now but now atlas size 8kby8k to fit all characters. Size is not my concern but will it affect performance negatively ?

 

Please watch the following two videos which cover specifically how to handle CJK including updated recommended workflows.

You should not be trying to create a font asset the includes all possible CJK characters but instead create static font assets that only contains the known characters used in the project. Then assign to these static font assets dynamic font assets designed to handle the unknown characters coming from other sources such as user input. This is covered in those videos.