Perhaps you should try some spelling variations:
operational conditions » operating conditions, operational considerations, operational definitions
marketing environment » market environment, making environment, modeling environment
environments » environmental

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: ((marketing environment) OR (learning environments)) AND operational conditions.
• Adding a wildcard symbol may retrieve word variants: ((marketing environment) or (learning environments)) and operational conditions*.