If you say the others have gone away with creams and what not...is it possible the ones that won't go away aren't so much "bumps" but scars? It's common for dogs of unknown origin to have some scars, even moreso if they're a bully breed. However the itchiness is a bit suspicious.
Have you tried changing her food? If you rescue you probably know Pits are prone to skin problems and some skin allergies, but sometimes a good, high quality food can help, especially grain free. I would consult a vet too if this gets worse. It could be this is a hot spot forming.
Have you tried changing her food? If you rescue you probably know Pits are prone to skin problems and some skin allergies, but sometimes a good, high quality food can help, especially grain free. I would consult a vet too if this gets worse. It could be this is a hot spot forming.