The quickest way to find a contact, whether or not they’re already in your Contacts list, is to start typing the person’s name, phone number, or email address in the search box.
To find a contact, from the contacts screen, tap the search icon at the bottom, and then start typing their name, phone number or extension, or email address in the search box. The results are shown below the box.
When Phonebook Integration is set to ON, then when you search for a contact, the search results will also find contacts on your mobile phone. You can go to settings and set the Phonebook Integration setting to on or off.