NL function - Link

Hi Everyone,
i am new in this and i need your help.

I have prepared this NL function:

=NL("Rows","Purchase Line","Document No.","Connection=",$F$2,"Company=",$F$3,"Type","Item","Link=","Purchase Header","No.","=Document No.","Document Type","=Document Type","Posting Date",$C$11,"Link=","Vendor","No.","=Buy-from Vendor No.","Grupo Proveedor", $F$6)

Where Grupo Proveedor is a field from the Vendor card.

I just want to know the "Document No." of the purchases within a "Posting Date" filtered by "Grupo Proveedor" field. This NL function is very slow and just show me one line. how will be it correct?

Thank you for your help!!