If your yard looks like a giant salad bowl filled with dandelion greens than there is no single weeding tool that is going to help you take back your lawn. To remove the problem you must remove the cause and in this case it is the soil. I have owned several homes and had to start a new lawn four times. Inheriting a lawn full of weeds is equally frustrating but it is a winnable war. The lawn in the picture below is not my lawn but my lawn did look a lot like it 3 years ago.