Those are terrible photos - almost impossible to distinguish what the weeds look like in that indistinct pulled clump. Next time take a careful shot of them growing in place.

As best as I can tell, that looks like ground ivy, Glechoma hederacea. That is an evergreen creeping vine that will invade lawns and flower beds. And any pre-emergent will have no effect on it.

Even a very lush, heathy lawn will have difficulty out competing ground ivy. Typically it will require the use of post emergence lawn herbicides containing dicamba, 2, 4-d and triclopyr (like Trimec). Fertilizing the law will only serve to fertilize the ground ivy as well.