When the system is configured against LDAP, we always load the email address and name from LDAP, never from the database. The problem is that these other users haven't set their email address and name as visible, which means you can't search for them. For your existing users, you can go to the admin console and change the visibility settings for email and name individually, but for new users you can set the following system properties:
both to 'true'.
After you do that any new users will automatically have their email and name visible.