I don't know what to do

Im div 16/17 and i got random match up sometime i get people that seem too god to be div 16/17 or cheeser and spammer (clinch kne amd elbow) only a few time i get good matchup i always wanted to reach div 20 but i don't know if i must play regardlees the matchup or play some other mode and try to get better with people around my level