I noticed the same problem with Scott's Weed and Feed ... if it doesn't get right on the weed, you have not necessarily killed it. Plus, the stuff is really expensive if you cover the entire lawn. Plus, plus, if you use it in a broadcast mode you are putting lots of chemicals on your lawn.
How about this: A water spray bottle in one hand and an old glass bottle with big holes stabbed in the lid. Fill the glass bottle with Scotts Weed and Feed. Just walk through the lawn and spray water on each weed (not that big a deal). Shake the W&F directly onto the weed so it adheres directly. This guarantees death to the weed and a minimum use of the chemicals.
For fertilizer, I but generic with a complete nitrogen-phosphorus-potassium ratio such as 21-7-14, 16-6-8. Some lawn guys like 15-15-15 but I get better results with the first two.
One other tip, I mow "high." I grow grass at its highest-recommended height to encourage a deep root system. Taller grass blades shade the soil to reduce moisture loss, protect the grass crown (growing points), and ensure blades will not wilt as easily when mowed. Lawns at their highest mowing heights grow more slowly, which in turn reduces water use and the need to mow.
BUT, taller lawns force weeds to grow upward, through the blades, which exposes the weed branch to weed killed!