Perhaps you should try some spelling variations:
"land management centers." » "land management controls.", "land management control.", "land management water."
"oxford management review." » "records management review.", "fund management review.", "road management review.", "oxford management reform."
"farm management review." » "farm management reform.", "cash management review.", "bank management review.", "data management review."
"demand management data." » "debt management data.", "demand management a.", "demand management case."
"flood management concepts." » "fund management concepts."
"firm management contracts." » "fire management contracts.", "city management contracts.", "care management contracts."

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: (((("oxford management review.") OR ("farm management review."))) OR ((((((("firm management contracts.") OR ("land management centers."))) OR ((("reform management _.") OR ("demand management data."))))) OR ("flood management concepts."))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"oxford management review.\") OR (\"farm management review.\"))) or (((((((\"firm management contracts.\") or (\"land management centers.\"))) or (((\"reform management _.\") or (\"demand management data.\"))))) or (\"flood management concepts.\"))))~".
• Removing quotes may allow a broader search: (((( oxford management review. ) OR ( farm management review. ))) or ((((((( firm management contracts. ) or ( land management centers. ))) or ((( reform management _. ) or ( demand management data. ))))) or ( flood management concepts. ))))~.
• Adding a wildcard symbol may retrieve word variants: (((("oxford management review.") OR ("farm management review."))) or ((((((("firm management contracts.") or ("land management centers."))) or ((("reform management _.") or ("demand management data."))))) or ("flood management concepts."))))*.