I keep shooting left with my bow.?

Recently i bought a used bow from the local bow shop. the bow is a Jennings Starmaster with a draw weight of 50lbs. The draw is 27 in. i use a whisker biscuit and a trueglow five pin sight. i use carbon arrows and have been shooting field tips so far. as much as i try to aim straight i always shoot left. when i first starting shooting the experts told me that the anchor was everything and as much as i focus on my anchor i always seem to shoot groups that are left. any tips?