Perhaps you should try some spelling variations:
"special effects models" » "special effect models"
"social exact model" » "social effect model", "social et model", "social email model"
"social etats model" » "social ethics model", "social etas model", "social rats model", "social beats 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 etats model"))) OR ("special effects models")).
• Removing quotes may allow a broader search: (((( social exact model ) or ( social etats model ))) or ( special effects models )).
• Adding a wildcard symbol may retrieve word variants: (((("social exact model") or ("social etats model"))) or ("special effects models"))*.