Perhaps you should try some spelling variations:
"national science series 2:, physics" » "natural science series 2:, physics", "spatial science series 2:, physics", "animal science series 2:, physics", "national science services 2:, physics", "national science stories 2:, physics", "national science theories 2:, physics"
"nato science series 10:, physics" » "nato science services 10:, physics", "nato science stories 10:, physics", "nato science theories 10:, physics", "radio science series 10:, physics", "nato science series 1:, physics"
"nato science series 3:, physics" » "nato science services 3:, physics", "nato science stories 3:, physics", "nato science theories 3:, physics", "radio science series 3:, physics"
"nato science series 2:, physics" » "nato science services 2:, physics", "nato science stories 2:, physics", "nato science theories 2:, physics", "radio science series 2:, physics"

Try widening your search to All Fields.

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: (((("nato science series 10:, physics") OR ("nato science series 3:, physics"))) OR ((("nato science series 2:, physics") OR ("national science series 2:, physics")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"nato science series 10:, physics\") OR (\"nato science series 3:, physics\"))) or (((\"nato science series 2:, physics\") or (\"national science series 2:, physics\"))))".
• Removing quotes may allow a broader search: (((( nato science series 10:, physics ) OR ( nato science series 3:, physics ))) or ((( nato science series 2:, physics ) or ( national science series 2:, physics )))).
• Adding a wildcard symbol may retrieve word variants: (((("nato science series 10:, physics") OR ("nato science series 3:, physics"))) or ((("nato science series 2:, physics") or ("national science series 2:, physics"))))*.