Perhaps you should try some spelling variations:
"groups generalized radiant" » "groups generalized gradient", "groups generalized radiance", "groups generalized gradients", "groups generated radiant", "groups general radiant"
"groups generalized radar" » "groups generated radar", "groups general radar", "groups generalized radon", "groups generalized random", "groups generalized rank"
"groups generating radar" » "groups generated radar", "groups generators radar", "groups operating radar", "groups penetrating radar", "groups penetrating radars", "groups generating random"
"groups generation radar" » "groups generated radar", "groups general radar", "groups generation raman", "groups generation radio", "groups generation random"

Try widening your search to All Fields.

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: (("groups generating radar") OR ((("groups generation radar") OR ((("groups generalized radar") OR ("groups generalized radiant")))))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"groups generating radar\") or (((\"groups generation radar\") or (((\"groups generalized radar\") OR (\"groups generalized radiant\"))))))".
• Removing quotes may allow a broader search: (( groups generating radar ) or ((( groups generation radar ) or ((( groups generalized radar ) OR ( groups generalized radiant )))))).
• Adding a wildcard symbol may retrieve word variants: (("groups generating radar") or ((("groups generation radar") or ((("groups generalized radar") OR ("groups generalized radiant"))))))*.