How to find invoice number

Do you have any problem, as long as you quickly tell us invoice number, we will have a corresponding sales for your perfect service.
You open the package, you will have a copy of our WINNI invoice list (HK) ELECTRONIC COMPANY is, above all information about our company, please keep it, because our service in it, above an invoice number, by the invoice number can be found in our corresponding sales staff, it will serve you, it is on the right COMMERCIAL iNVOICE, it will begin with A.B.C.D.E.F.D.H to + four or five numbers, each letter represents our company's sales staff, each number represents invoice column number, because our sales staff more, I hope you can tell us the invoice number, we will be more party for you.