Overview

You are able to filter custom fields through members on your site through the Member Directory module.

Prerequisites

• Access to a Superuser account.

Solution

Once you've created a custom field for the users from Settings > Site Settings > Site Behavior > User Profiles > Add Field. 

Don't forget to click Next and set the Field Name to whatever you want to display in the search.

 This is an example of a Member Directory module:

Now, if you want to change the terms of Advanced Search you can do it from the module settings:

*Note that the name of the field is the one you used on the second screen while creating the variable.