find out
To learn or discover (something you did not know before.)
One morning the baby found out for the first time that she could walk.
I don't know how this car works, but I'll soon find out.
He watched the birds to find out where they go.
Mary was angry when Jane found out her secret.
To get facts; to get facts about.
He wrote to find out about a job in Alaska.
She found out how much the house would cost.
Will you please try to find out what time the airplane arrives?
I'll call right now to find it out.
To discover (someone) doing wrong; catch.
Some children are bad when no one is watching them, but they are usually found out.
The boy knew that if he cheated on the test the teacher would find him out.
finders keepers
finders keepers, losers weepers
Those who find lost things can keep them. Used usually by children to claim the right to keep something they have found.
I don't have to give it back; it's finders keepers.
Finders keepers, losers weepers! It's my knife now!