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

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