Breastfeeding mom in need of help?

I am breastfeeding a 2 month old baby. My milk supply is very low. In the mornings i can pump 2oz from both breast after that through out the day hen i pump if I'm lucky i'Ll pump 1oz from both. Does anyone know what i can do to increase my supply. I've heard of some milkshakes that i can drink. Does anyone know of any? Or anything to help my increase.