Perhaps you should try some spelling variations:
"national science theories b:, physics" » "natural science theories b:, physics", "animal science theories b:, physics", "natural sciences theories b:, physics", "national science three b:, physics", "national science theories 3:, physics", "national science theories 4:, physics", "national science theories 1:, physics"
"spatial science theories b:, physics" » "spatial science three b:, physics", "social science theories b:, physics", "spatial science theories 3:, physics", "spatial science theories 4:, physics", "spatial science theories 1:, physics"
"nato science theory b:, physics" » "radio science theory b:, physics"

Try widening your search to All Fields.

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• If you are trying to use Boolean operators, they must be ALL CAPS: (((("national science theories b:, physics") OR ("spatial science theories b:, physics"))) OR ("nato science theory b:, physics")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"national science theories b:, physics\") OR (\"spatial science theories b:, physics\"))) or (\"nato science theory b:, physics\"))".
• Removing quotes may allow a broader search: (((( national science theories b:, physics ) OR ( spatial science theories b:, physics ))) or ( nato science theory b:, physics )).
• Adding a wildcard symbol may retrieve word variants: (((("national science theories b:, physics") OR ("spatial science theories b:, physics"))) or ("nato science theory b:, physics"))*.