Welcome to the board... I am seeing some slow growers in that area of thin coverage so I'm guessing with them coming in and surrounding hairs taking on length, that side should become acceptable in a few months. Stick with it. I looked at the ingredients of the product recommended for increased growth above and it's mostly oils that IMO will not do much to improve coverage... you could try it, but time and patience is your better ally. Good luck. 

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