Thanks Pixelbypixel and Erin,
I think it's the fundamental of SEO market in Chinese, Japanese, Korea. But, I am not sure it's related to UTF-8 code page ? My page is UTF-8. I guess it's related the 'phase' of the sentence. It's hard to make index by a simple rule. Moz parser engine don't know a phase is composed of 2 or 3 or 4 characters in a sentence.
For example: "專案管理" , "專案" means 'Project' , "管理" means 'Management', but "專" "案" "管" "理" each single character will be used in other sentences but with different meanings.
It's complex, I think google knew the rule very well. But, at least, you don't need to count each character. Because we will put the keyword by ourselves, we just want to know a phase "專案管理" , we don't care them separately.
Chinese and Japanese market is huge, why don't you hire a asian engineer to do such research ? The ROI will be great !
William