You can say that again
Your guess is as good as mine
Your Guess Is as Good as Mine
Your name is mud
You can’t have your cake and eat it too.
You can lead a horse to water but you can’t make it drink.
You show me the man and I’ll show you the rule.
You can’t take it with you
You can catch more flies with honey than with vinegar.
You can’t teach an old dog new tricks.