Perhaps you should try some spelling variations:
"line groups" » "line group", "life groups", "linear groups"
"link groups" » "sink groups", "risk groups", "disk groups"
"like groups" » "large groups", "crime groups"
"lie groups" » "life groups", "live groups"

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: (((("line groups") OR ("link groups"))) OR ((("like groups") OR ("lie groups")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"line groups\") OR (\"link groups\"))) or (((\"like groups\") or (\"lie groups\"))))".
• Removing quotes may allow a broader search: (((( line groups ) OR ( link groups ))) or ((( like groups ) or ( lie groups )))).
• Adding a wildcard symbol may retrieve word variants: (((("line groups") OR ("link groups"))) or ((("like groups") or ("lie groups"))))*.