Anyone can explain me how grazing hit works?

[Eddexp]

before I thought to have little hit and not have proeficience with the weapon i was missing a few blows however this life tried to increase the maximum hit with my bow and still happens more grazing hit then my other character with a melee weapon. I reached 110 hit with the bow and 80 with swords and test with same mobs. After that i test with the same character eho has 110 hit with rthe bow and 85 with the sword and still get more grazing hits wit the bow. That mecanic are bother me cuz i loss mostle of the arcane archer elemental dmg with that.