How to use Labtalk in Origin(fit peaks in loop and export datas to .csv)

Question

 loop(n,3,5){
fitpeaks iy:=[Book1]Sheet1!(1,$(n)) np:=1 rd:=<new name:=$(n);
expExcel c:\Users\Book1.xls;

}

I'm trying to automate OriginPro using labtalk programming. Code's purpose is to find peak and get fitted data worksheet as csv file I keep failing to name the Workbook and sheets

anybody know how to designate the new fitted data worksheet's Book? I want to get the fitted data worksheet in one Workbook like [Book1]Sheet3 [Book1]Sheet4