Perhaps you should try some spelling variations:
"groups generation radar" » "groups generated radar", "groups generalized radar", "groups generation raman", "groups generation radio", "groups generation random"
"groups general radar" » "groups generated radar", "groups general reader", "groups general readers", "groups general randers"

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: "((\"groups generation radar\") OR (\"groups general radar\"))".
• Removing quotes may allow a broader search: (( groups generation radar ) OR ( groups general radar )).
• Adding a wildcard symbol may retrieve word variants: (("groups generation radar") OR ("groups general radar"))*.