Hi,
It is expected behavior. Please check whether the user "Mohd Rudian Abdullah" is added as Contact for this user.
Generally, when the user searches Global Address List in Address Book with Last Name and First Name, the search results can be returned. But it can't be searched with partial name.
If you add it as a local Contact for the user, when search the Contact instead of GAL in Address Book, it can be searched and filtered out with partial name. In OWA, it would search the user in Contact by default. Please click Directory and check whether
you can search this user with partial name or not.
Regards,
Winnie Liang
TechNet Community Support
