you can't squeeze blood from a turnip

proverb It is impossible to obtain something from someone if they are too parsimonious, uncharitable, or resolved against it. I've tried everything to get my toddler to eat vegetables, but you can't squeeze blood from a turnip. I give up. Good luck trying to get Dad to give you the money. You can't squeeze blood from a turnip. If you think I'll give you the information you're looking for, you're sorely mistaken! You can't squeeze blood from a turnip!