Perhaps you should try some spelling variations:
"american ecological associations" » "american clinical associations", "american psychological association", "american ecological applications", "america ecological associations", "american urological associations", "american technological associations"
"american political associations" » "american clinical associations", "american political assassination", "american political observations", "american politics associations", "america politics associations"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"american ecological associations\") OR (\"american political associations\"))".
• Removing quotes may allow a broader search: (( american ecological associations ) OR ( american political associations )).
• Adding a wildcard symbol may retrieve word variants: (("american ecological associations") OR ("american political associations"))*.