Perhaps you should try some spelling variations:
"social exact model" » "social effect model", "social etats model", "social et model"
"social state model" » "social status model", "social side model", "social study model"
"social seat model" » "social start model", "social great model", "social smart model", "social seats model", "social swat model", "social sea model"

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: (("social exact model") OR ((("social seat model") OR ("social state model"))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"social exact model\") or (((\"social seat model\") OR (\"social state model\"))))*".
• Removing quotes may allow a broader search: (( social exact model ) or ((( social seat model ) OR ( social state model ))))*.