Felicia,
Cod liver oil has fair amounts of Vitamin A (preformed kind) and Vitamin D. Be sure to check your label. It's also a good source of essential fatty acids, specifically Omega 3's. You just don't want to overdo it with cod liver oil. And, remember it is derived from the cod's liver...not a great source in terms of purity. You might want to choose Carlson specifically for this reason. It's some of the best. Same thing with their fish body oils.
With the ginger, for your hair specifically, it is fairly stimulating and encourages moisture retention. It's also excellent for immunity and when you have an actual cold/flu to ease it a bit.
~Jade~