Perhaps you should try some spelling variations:
"social effects models" » "special effects models", "social aspects models", "societal effects models", "local effects models"
"social effect models" » "societal effect models", "special effect models", "local effect models"
"social net model" » "social news model", "social na model", "social needs model"
"social set model" » "social seat model", "social asset model", "social self 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 net model") OR ("social set model"))) OR ((("social effects models") OR ("social effect models")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"social net model\") or (\"social set model\"))) or (((\"social effects models\") OR (\"social effect models\"))))".
• Removing quotes may allow a broader search: (((( social net model ) or ( social set model ))) or ((( social effects models ) OR ( social effect models )))).
• Adding a wildcard symbol may retrieve word variants: (((("social net model") or ("social set model"))) or ((("social effects models") OR ("social effect models"))))*.