Here is how to create a custom segment within Google Analytics in order to segment any call tracking data you may have on a specific phone calls URL (or any other URL).
Log into Google Analytics and go to your Reporting tab
Expand "All Visits" and click on "Create New Segment"
Name your custom Segment and click on "Conditions" under the "Advanced" section.
Filter on "Landing Page" contains and enter the URL of your phone calls page
Click on Save