Perhaps you should try some spelling variations:
"military operational" » "military operations", "military cooperation", "military observations"
"military personal" » "military pensions", "library personal", "military lessons"
"military persons" » "military pensions", "military lessons", "military weapons"

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: (("military personnel") OR ((((("military personal") OR ("military persons"))) OR ("military operational")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"military personnel\") or (((((\"military personal\") OR (\"military persons\"))) or (\"military operational\"))))".
• Removing quotes may allow a broader search: (( military personnel ) or ((((( military personal ) OR ( military persons ))) or ( military operational )))).
• Adding a wildcard symbol may retrieve word variants: (("military personnel") or ((((("military personal") OR ("military persons"))) or ("military operational"))))*.