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 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.

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