Do you understand the difference between a label and a material document?
A material document is the thing that is created when you post a receipt and has usually exact the same information. You can have a separate one per item or a collective with all items.
You can print just 1 copy or you define several copies, one for your files, one for the receiver etc etc.
A label is the thing that put on the parcel or drum to add internal information additionally to the labels that are already there from your vendor. I would say one label is usually sufficient, a copy may be needed if you want put the same information on the backside or on top of a parcel or drum, so that it can be read from any position.
Please go through one of the best wikis in SCN: Output Determination in Inventory Management (IM) - ERP SCM - SCN Wiki to analyze where you went wrong