I was never able to make any sense out of the following Japanese proverbs or idiomatic expressions:
豆腐の角に頭をぶつけて死んでしまえ。
'Hit your head against a corner of a cake of tofu, and die.'...の爪の垢を煎じて飲む。
'take extract from one's dirt/wax under the nail, and drink it'
They are nonsense to me, and the latter is also disgusting. How can you die in such a way? What is the purpose of drinking such thing? How can you make a sense out of them?