There is no secret method. Even the professional callers use different calls or sequences every time they sit down. They base there technique on everything - ie location, time of year, time of day, how educated the coyotes are, wind, and I'm sure there is more. It sounds like your in a tough spot because the more you call, the smarter those coyotes get. They also depend on their nose which is by far and large a big part of why we can't get them to come in over here on the wet side. I couldn't tell you how many times out on the east side I have had coyotes sit on their rump and just stare in my direction 400yds 500yds and beyond. They hear me just fine and I would bet the dinner I offer them sounds just mighty tasty, but they smelled me. Game over. Hunting over here in the trees we probably have twice the coyotes as the east side of the state but we just can't see them. I really can't offer any advice other than to pay attention to the wind, pay attention to every little movement you see, be as sneaky as you can getting to the set, and don't be afraid to try different calls or sequences. I would highly recommend you try and find some coyote hunting seminars too. Good luck