Active Directory users don't show when trying to add/search as new user/people

Hi,

I'm having problem with my SharePoint 2013 people picker. It doesn't shows any AD users at all.

But strangely, when I pick/search people in its Central Administration site, all my AD users are shown.

Both of the site are on the same server and of course were installed as a same package of sharepoint installation.

Did I missed something? I have done previously installation of SP2010, but never came across this problem.

Thank you so much for your help... :)