You'll need to change your search preferences. To do this, follow the instructions below.
1. Navigate to the MMS.
2. Once you are logged in, you should see your name in the top right corner followed by links. Select the "Preferences" link.
3. The screen will change to display User Preferences. About halfway down the screen you should see a heading that says "Search Preferences".
4. Change the preference from "Your Default Groups" to "Whole Contact Database"