Perhaps you should try some spelling variations:
"german aerospace cluster" » "german aerospace system", "emc aerospace cluster", "global aerospace cluster", "german aerosparse cluster", "german aerospark cluster", "german aeroface cluster"
"german aerospark cluster" » "german spark cluster"
"german space cluster" » "german sparse cluster", "german spark cluster", "german face cluster", "bergman space cluster", "german spa cluster", "german stage cluster"

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: (((("german aerospace cluster") OR ("german aerospark cluster"))) OR ("german space cluster"))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"german aerospace cluster\") OR (\"german aerospark cluster\"))) or (\"german space cluster\"))*".
• Removing quotes may allow a broader search: (((( german aerospace cluster ) OR ( german aerospark cluster ))) or ( german space cluster ))*.