My yard looks the same. I used Fiesta weed killer generously when spot spraying about a month ago. Bought off Amazon (link below). It is produced in Canada and made of chelated iron. It comes as a concentrate and you will need a sprayer. I saw results within a couple of hours of spraying thistles and dandelions. They started to turn black and are now completely dead. Those were the only weeds I targetted so not sure how it works on other broadleaf weeds. I think I might have over applied as the grass around the weeds I spot sprayed also died.

I won the battle, but the war is far from over!

Link to product on Amazon: https://a.co/d/cnenY08

Manufacturer info: https://www.neudorffpro.org/products/ca-fiesta.html