Perhaps you should try some spelling variations:
"ambulance" » "ambulanten"
"imbalance" » "imbalances", "balance"
"ambulanter" » "ambulanten", "ambulantenr"
"ambulantenr" » "ambulanten", "ambulantes", "ambulanzen", "ambulantennr"
"ambulante" » "ambulanten"

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: (("ambulance" OR "imbalance") OR (("ambulanter" OR "ambulantenr") OR "ambulante")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"ambulance\" OR \"imbalance\") or ((\"ambulanter\" or \"ambulantenr\") or \"ambulante\"))".
• Removing quotes may allow a broader search: (( ambulance OR imbalance ) or (( ambulanter or ambulantenr ) or ambulante )).
• Adding a wildcard symbol may retrieve word variants: (("ambulance" OR "imbalance") or (("ambulanter" or "ambulantenr") or "ambulante"))*.