You could try Weed-b-Gon Chickweed, Clover, and Oxalis Killer. See those purple flowers? The weed is reseeding itself. That means it will come back from seed after you kill it off. You have to be vigilant and spot spray every time you see it coming back.

Those are violets. Many find them desirable but they DO spread. The suggested product will work well to control when used as directed.

Personally, I find them attractive. But then I am not a pure lawn fanatic and I gladly tolerate the modest invasion of wildflowers that appear in my lawn - lawn daisies, violets, yarrow, wild strawberry, clover. etc. There's even some hardy cyclamen, ajuga and crocus growing here and there. I only remove obvious perennial weeds like dandelions, plantains, dock, etc. and I do that by hand.

Thank you.