noise and coockies

Noise functions were somewhere years ago in Physics lessons at school. I was fond of physics. I liked curves and representation of sound as a curve and the possibility to show sound interposed one over the other. This is what noise is about. How come we cannot hear a sound when there is noise?
Can I hear something when I eat a coockie? Or many coockies? Or most coockies? When I drink? I rarely drink too much (less than once in 5 years), being a responsible parent. I'm affraid I drank too much coffee, and if I drink too much coffee I'm more likely to loose my sense of humor.