Sniffers......

Ok guys, maybe this year isn't going to be like last year but even last year we could coax the sniffing walleye into biting after working them for a bit. We have been out 5 times so far and I myself have only caught a limit twice. What's the scoop with these eyes at this time? I can have a mark come up off the bottom and I will work him and work him for 5 minutes only to have him swim away. I've tried changing as usual.... lures/colors/sizes/speed. What gives? Also when we get to our spots in the morning we mark and mark fish but no takers! We always end up moving to somewhere with less marks. Should we wait them out until they bite or are we doing right by moving? Any help would be appreciated.