Retrieves the batches, serial numbers and untraced quantity a sales return row can still take back: shipped on its sales order row and not taken by another sales return row or an already restocked return. An entry with neither a batch nor a serial number is the quantity shipped untraced, which the rows of a return share. batch and serial_number give the details of the batch or serial number of an entry, and are null when it has none. Pick entries from this list for the traceability of the row.