“If you’re not sure if the dog has something or not, don’t ask it if it has anything. You may talk the dog into an alert. Let the dog make up its own mind.

Leave the area of greatest interest, search other areas or take a break, then bring the dog back in. Try to approach from another direction. Observe what your dog does without cueing from you; sometimes the dog will have no further interest in the area. – Marcia Koenig”