Vlookup VBA

Hello everyone,

I would need some help finding what's wrong with my code please.

VLOOKUP( value, table, index_number, [not_exact_match] ) : here the value is in another workbook (so I'd like my result to be written in another workbook).

My code :

Sub exp()

Dim db As Workbook
Set db = Workbooks("wk46prod")


db.Worksheets("Packing Schedule").Range("G13") = _
Application.WorksheetFunction.VLookup(db.Range("G28"), Workbooks("vba stock").Worksheets("feuil1").Range("B9:d18"), 3, False)


End Sub

thank you v much in advancz