When CSV where encoded as UTF-8 then it will not work for china language .
There will be another encoding for china language that will work in WPS as perfectly but not in EXCEL
GB2312 and GB18030
For csv file creating the whole code snippet will be as follows.
var fileObj = file.create({
name: fileName,
fileType: file.Type.CSV,
contents: csvFileData,
encoding: file.Encoding.GB2312,
});