Would it be possible to make the thin hair (on my hairline only) thick? (Photos)

At present, I am on finasteride and have seen positive results. However, my hairline at the temples and sides is still quite thin. I do not want to lower the line but would it be possible to make the thin hair thick? Or would the result be not very effective? How would I best find a doctor in the Los Angeles area? What should I look for?