Not sure how to do it on your phone…but on a computer it's pretty easy:
Click on "Community" in the blue bar at the top of the page >
Select "Members List" >
Click on "Search Members" in the second blue bar towards the right >
Select "Advanced Search">
Enter/Select the City &/or State you are looking for in the boxes provided. You not need to fill in all the criteria, just the search filters you want to use >
Scroll to the bottom & click "Search Now"
The members within your search criteria will appear.
I know the phone app interface programs work differently and may not have all the same features. They strip some stuff out to make better simplified phone viewing. If that's the case, you can log on through your internet browser on your phone instead and it looks just like on a computer, but smaller.