I found this YouTube video that explains what not to do when Crossing U.S. Canadian Border.
Border guards choose who to search based on appearance and demeanor. The appearance and demeanor you want to present is, “I am law-abiding and I recognize your authority.” Even if that isn’t the whole truth, it is what you want the border guard to believe. A border crossing is not where you want to ‘exercise your rights’.
You will find more detailed information on this website.