Perhaps you should try some spelling variations:
crop adoption » erp adoption, crop adaptation
die adoption » die adsorption
era adoption » ema adoption, esa adoption, a adoption
der adoption » user adoption, _ adoption
energy crop » energy crops
energy die » energy diet, energy due, energy dis

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: "((((\"energy crop adoption\") or (\"energy die adoption\"))) or (\"energy ((era adoption) OR (der adoption))\"))".
• Removing quotes may allow a broader search: (((( energy crop adoption ) or ( energy die adoption ))) or ( energy ((era adoption) or (der adoption)) )).