In addition to correcting the RBC/hematocrit, B12 can also help normalize the white cells. Nutrients that play a key role in blood production are B12, folate, B6, iron, copper and zinc. These are just the heavy hitters. So in addition to the B12, you may want to add in a B-complex that has the bio-available form of vitamins. And if you haven't already, at some point, get your copper, iron and zinc tested. I would NOT supplement with iron or copper until you know what they are.

You really can't draw any definitive conclusions from just one blood draw unless they are really out of range. Even then, you need to rerun the tests again. You would be surprised at how easily they mess up a blood draw.