Q.natural Weed and Grass killer
Is there any type of Weed and Grass killer that I can use that will not kill the Wooly Thyme ground cover that is in the same area? Thanks.

Unfortunately if you use a weed killer and it touches the Wooly Thyme is will kill it also.
You can try to carefully spray a weed if your unable to pull them successfully, but it is nearly as tedious as pulling the weeds.
Here is a link about growing Wooly Thyme.
Encouraging good growth can certainly help choke out weeds.
https://www.gardeningknowhow.com/edible/herbs/thyme/woolly-thyme-ground-cover.htm