I'm assuming your not growing it as a crop and want to know the best way to kill it.
My 2 cents:
Ortho (any big box store) makes some good weed killers.
One day I looked at the weed-killers I had in the garage.
Why so many ? ? ? What's the difference ? ? ?
It was confusing. Then I read the ingredients.
It looks like the active ingredients are derived from the "salts of different acids".
Your typical Broad-Leaf-Weed killer contains 0.5% active ingredient.
For a little tougher weed, it's 8.0%
For the toughest weeds, 17.0%
Different products, different salts of acids, different %'s
Spray too much, grass will start to die, but does grow back.
When I wanted to get my lawn in better shape, what worked good for me was:
1) Spray with a Weed-N-Feed using a garden hose and spray the whole lawn.
This gave good coverage and got rid of most weeds.
Repeat 2 Weeks later.
2) Buy some weed-killer in concentrate form and spot treat the tougher weeds using a pump sprayer.
It's a balancing act between weed control and using minimum amount of chemicals.
Good luck.