There is no product that will kill everything apart from the Pachysandra. The exception being if the 'weed' is a grass and then you can get a selective weedkiller.

Sounds as if the way forward is to get out there and hand weed.

Pachysandra is usually considered a weed smothering plant - is yours a bit thin?

I understand. Our pachy is pretty thick and the weeds are really only on the fringe of an area where a tree used to be. Many of the "weeds" are little saplings that shoot up from the old tree roots. But, there are some other weeds mixed in. Wanted to avoid the dreaded weeding but I guess I have no choice - thank you !!!!

If you can keep the weeds at bay for the time being the Pachysandra should move into the area gradually and relieve you of the deweeding duty.

Pull any weeds and then use a pre-emergent like Prodiamine all over the area. A strong Prodiamine application can prevent weeds from seeds for 8 months. Apply twice per year and never weed again.