Dreams or visions about picking your nose tell you that you are trying to remove old pains, physical displeasure, character traits, bad and good habits from your life. You are deliberately removing things, but the question is whether this way of cleaning is the correct choice and way. Another explanation is that you have a childlike view of life and apply the imitation reaction in your life, I want what you have too.
Blowing your nose in your dream or vision tells you that you want to get rid of an unhealthy situation in your life. You must learn to express the unhealthy energy, you must leave it behind. Another explanation is that you become detached from old patterns and become aware of your own behavior or situation in which you play a leading role yourself. A dream or vision like this also tells you about becoming aware of old habits with which you are really done.