You can edit .csv files in Streaming Assets folder. Excel file doesn't save Chinese characters, so you will need to find alternate ways of doing it.

Here's a little example of what you should do. Like shown in this image below you have to edit text in third column. You can edit the one in second column to but don't mess with first column  as it's essential to find the text key.

If you do it correctly you should see something like this.