Perhaps you should try some spelling variations:
social effect » social effects, societal effect, special effect
social exact » social etats, social email, social era
rats model » rat model, rate model, ratio model
etas model » keras model, gas model, das model
social et » social en, social e, social etats

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) OR (social effect))) OR (social et)) model ) OR ( social ((rats model) OR (etas model)) )).
• Adding a wildcard symbol may retrieve word variants: (( ((((social exact) or (social effect))) or (social et)) model ) or ( social ((rats model) or (etas model)) ))*.