Powerful laundry detergents?

I really need help so most of my daughters clothes are stained with oil stains from her father and her grandfather picking her up after coming out of work (they are tow truck drivers) I have tried multiple washes to get the stains out and they still won’t come out and I would just be throwing away money if I just tossed the clothes out do you guys have any suggestions of laundry detergent that can take these bad stains out anything can help please just let me know