How to get stubborn stains out of clothes

Mr

My daughter is a messy eater, all of the stains are food stains, not poop lol. My washer is really good and I try deep wash, extra soak, etc and the stains still don't come out 😵 Here's some examples.

If it's a product like oxyclean (I think that's what it's called?) how do I use it?