What does the constitution say is the supreme law of land

The "Supreme Law of the Land" is mentioned in Article VI of the Constitution, in the "Supremacy Clause". It names the Constitution itself the "Supreme Law of the Land" : other laws in the country are secondary to it and may not conflict with it.

You can drink laxative, or  do this exercise when you are sitting in the bathroom on the toilet. to relieve  constipation  fast or in about 1 minute, pinch your nose after your usual exhalation. start holding your breath. but do not mouth breath during this just hold your breath.