Will it kill thick woody weeds
This article on Natural Weedkillers is really helpful
We use a vinegar, epsom salt, dawn mix: https://thekitchengarten.com/diy-weed-killer/
Pull them out, trying to get the roots. Don't shake the soil off the roots, as there might be seeds from the weed in the soil
Hand pulling or brush killer spray.
If you're trying to get rid of an area of weeds, you can also cover them in a thick tarp, and allow them to die before removing it. It would take a few weeks. Good luck!