Perhaps you should try some spelling variations:
"psychiatrische" » "psychiatric"
"psychiatrisches" » "psychiatrics", "psychiatrischer", "psychiatrisch"
"psychiatrischen" » "psychiatricn"
"psychiatrists" » "psychiatric"
"psychiatrie" » "psychiatric", "psychiatry"

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: ((("psychiatrische" OR "psychiatrists") OR "psychiatrie") OR ("psychiatrisches" OR "psychiatrischen")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((\"psychiatrische\" or \"psychiatrists\") or \"psychiatrie\") or (\"psychiatrisches\" OR \"psychiatrischen\"))".
• Removing quotes may allow a broader search: ((( psychiatrische or psychiatrists ) or psychiatrie ) or ( psychiatrisches OR psychiatrischen )).
• Adding a wildcard symbol may retrieve word variants: ((("psychiatrische" or "psychiatrists") or "psychiatrie") or ("psychiatrisches" OR "psychiatrischen"))*.