Chinese and Japanese characters are not shown properly on iOS

I use Chinese, Korean and Japanese keyboards on my iPhone, but I found out that some of Chinese and Japanese characters are not shown properly. For example, when I tried to type in (せいしん or jingshen), the conversion candidate on the top of the keyboards showed 精神, not the correct Chinese characters. I think the problem might be that I use Korean as the main language. But then is there any way to type in the correct word on Chinese and Japanese keyboards?