Perhaps you should try some spelling variations:
"land management contracts." » "land management controls."
"land management contract." » "land management control."
"land management agency." » "land management agencies.", "land management science.", "land management areas."
"land management entity." » "land management energy.", "land management activity.", "land management quality."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((((("land management agency.") or ("land management entity."))) or ((("land management concepts.") or ("land management contracts."))))) or ("land management contract."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((((("land management agency.") OR ("land management entity."))) OR ((("land management concepts.") OR ("land management contracts."))))) OR ("land management contract.")).
• Removing quotes may allow a broader search: (((((( land management agency. ) or ( land management entity. ))) or ((( land management concepts. ) or ( land management contracts. ))))) or ( land management contract. )).
• Adding a wildcard symbol may retrieve word variants: (((((("land management agency.") or ("land management entity."))) or ((("land management concepts.") or ("land management contracts."))))) or ("land management contract."))*.