be on the lookout for

US /bi ɑn ðə ˈlʊkˌaʊt fɔr/
UK /bi ɑn ðə ˈlʊkˌaʊt fɔr/
"be on the lookout for" picture
1.

estar atento a, estar buscando

to be actively watching or searching for something or someone

:
We need to be on the lookout for any suspicious activity.
Tenemos que estar atentos a cualquier actividad sospechosa.
The police are on the lookout for the escaped prisoner.
La policía está buscando al prisionero fugado.