I'm new to crappie fishing and I've been spending a lot of time at the local lake tring to find and mark structure that might hold crappie.This past saturday my son and I bought some minnows and went to try our luck. We caught 19 keepers in about 3 1/2 hours but the thing that puzzles me is the structure I marked showed a bunch of fish that would not bite. Most of the fish we caught were about 100 ft away from the big cover. What's up with this?