You control what is on a 1099 by adding or excluding expenses on each eligible vendor through the 1099 wizard. To be able to separate expenses for a vendor you need multiple expense types for said vendor. And these are you COA expense accounts, not items.
And when in doubt, do not exclude anything. If you can prove you paid a vendor you can include all you paid. That is not considered an inaccurate 1099 subject to penalty.