Oracle HR R12.1.3 - Issues searching people with preferred names

Hi,

When searching for a person using their full name for example: Smith, Delia without any wildcards, the application will only bring back all the records with the same name who have not entered a value in the 'Preferred name' field.

If a 'Smith, Delia' has a value entered against the 'Preferred name' field and a user searches for this person it won't bring back any Delia's whom have a preferred name in the search box. It will only bring back those that do not have a preferred name saved against their record.

Is this normal or is there a profile option to sort this out?