Perhaps you should try some spelling variations:
"national science series 12:, physics" » "natural science series 12:, physics", "spatial science series 12:, physics", "animal science series 12:, physics", "national science services 12:, physics", "national science stories 12:, physics", "national science theories 12:, physics", "national science series 10:, physics", "national science series 11:, physics", "national science series 3:, physics", "national science series 32:, physics"
"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", "national science series 3:, physics"
"nato science series 1:, physics" » "nato science services 1:, physics", "nato science stories 1:, physics", "nato science theories 1:, physics", "radio science series 1:, physics", "nato science series 3:, 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 1:, physics") OR ((("national science series 12:, physics") OR ("national science series 2:, physics")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"nato science series 1:, physics\") or (((\"national science series 12:, physics\") OR (\"national science series 2:, physics\"))))".
• Removing quotes may allow a broader search: (( nato science series 1:, physics ) or ((( national science series 12:, physics ) OR ( national science series 2:, physics )))).
• Adding a wildcard symbol may retrieve word variants: (("nato science series 1:, physics") or ((("national science series 12:, physics") OR ("national science series 2:, physics"))))*.