dumb luck

as luck may have it

Synonym of as luck would have it (“by chance, luckily”).

be in luck

To be lucky in getting something that one wants.

better luck next time

Used to wish somebody hope in future success after a failure.

devil's luck

astounding good luck.

down on one's luck

Unlucky or undergoing a period of bad luck, especially with respect to financial matters.

dumb as a post

Utterly mute; lacking the ability to speak.

dumb down

To convey some subject matter in simple terms, avoiding technical or academic language, especially in a way that is considered condescending.

dumb shit

Alternative spelling of dumbshit.