Perhaps you should try some spelling variations:
"comparative management systems model" » "compensation management systems model", "comparative management system model", "comparative management system models", "comparative management systems modeling"
"communicating required resources history" » "communication required resources history", "communicating requirements resources history", "communicating research resources history", "communicating related resources history", "communicating liquid resources history", "communicating required measures history", "communicating required resources sector"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("comparative management systems model") or ("communicating required resources history"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("comparative management systems model") OR ("communicating required resources history")).
• Removing quotes may allow a broader search: (( comparative management systems model ) or ( communicating required resources history )).
• Adding a wildcard symbol may retrieve word variants: (("comparative management systems model") or ("communicating required resources history"))*.