leave no stone unturned

/lˈiːv nˈəʊ stˈəʊn ʌntˈɜːnd/

/lˈiːv nˈoʊ stˈoʊn ʌntˈɜːnd/

to leave no stone unturned

to do everything one can in order to achieve a goal, particularly when it involves finding or looking for something

Examples

1. He left no stone unturned in his search for his natural mother.

2. Since he still loves her, he is leaving no stone unturned to make her fall in love with him again.

3. If Sue noticed a change that quickly, I wanted to be sure to leave no stone unturned.

4. The full force of the FBI is investigating the heinous acts we saw last week, and we will leave no stone unturned.