Perhaps you should try some spelling variations:
"mail's depressive disorder" » "mail's impressive disorder", "mild depressive disorder", "manisch depressive disorder"
"und depressive disorders" » "und depressiver disorders", "und depressiven disorders", "und depression disorders"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("mail's depressive disorder") OR ("und depressive disorders"))*.
• Removing quotes may allow a broader search: (( mail's depressive disorder ) or ( und depressive disorders ))*.