There are several reason why Vlingo may not be able to find a contact:
There is more than one contact with the same last name. Please use the First and Last name to differentiate contacts.
You are searching for a Nickname which Vlingo does not recognize. Please use the First Name and Last Name to identify your contact.
Vlingo did not spell the contact name correctly. Please click on the name and correct the spelling. Vlingo will learn from its mistakes and recognize the contact when you try again.