search box

Hi guys,
I am looking for a plug-in that allows the search by city of users registered on a site.
I give an example:
50 users have signed up to a site by also entering the name of the city in which they live.
A user, who is not signed up to the site, has to look for someone close to him.
By entering the name of the city in the search bar, the person or persons of the same city exits.
Is there anything I can use?

Thanks in advance