Perhaps you should try some spelling variations:
"motivational states" » "motivational systems", "motivation state", "motivational system"
"motivational scale" » "motivational case", "motivational state", "motivational social"
"motivation scale" » "motivation state", "motivation scene", "motivation soziale"

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: (("motivational states") OR ((("motivational scale") OR ("motivation scale")))).
• Removing quotes may allow a broader search: (( motivational states ) or ((( motivational scale ) or ( motivation scale )))).
• Adding a wildcard symbol may retrieve word variants: (("motivational states") or ((("motivational scale") or ("motivation scale"))))*.