Your guess is as good as mine
You can’t fit a round peg in a square hole.
You can say that again
Your name is mud
You can’t have your cake and eat it too.
You can catch more flies with honey than with vinegar.
You show me the man and I’ll show you the rule.
Your Guess Is as Good as Mine
You can lead a horse to water but you can’t make it drink.
You can’t make an omelet without breaking eggs.