It may be kerotosis pilaris. I'm not entirely sure you might want to check with a dermatologist. I'm not sure what you do in the way of exfoliation. There's a product called glytone that uses 17.5% glycolic acid (which is used in some chemical facial peels) and it should offer a deeper exfoliation (I mean not a superficial exfoliation like you get from body washes with exfoliating beads or DIY methods) and should reduce the appearance. Have you always had these since you were a child? Before spending money on seeing a doctor, I really suggest you try Glytone which should be about 30 USDs on amazon (only on your body though) , if you don't see any results in 2-3 weeks then you should opt for a dermatologist.

Thank you, I will try Glytone but it seems expensive though and I have had this since 3-4 years ago (if that helps). But thanks anyways :D

Sorry to bother you again, but I did some short research about keratosis pilaris and I noticed that the symptoms are red bumps and itchiness but it does not itch and it is not bumps, they're just dark spots.