Perhaps you should try some spelling variations:
"nato science theories 2:, physics" » "nato science theory 2:, physics", "nato science three 2:, physics", "national science theories 2:, physics", "nato science theories 3:, physics", "nato science theories 4:, physics", "nato science theories 1:, physics"
"nato science series 2:, physics" » "nato science services 2:, physics", "nato science stories 2:, physics", "nato sciences serious 2:, physics", "national science series 2:, physics", "nato science series 3:, physics"
"radio science series 2:, physics" » "radio science services 2:, physics", "radio science stories 2:, physics", "radio sciences serious 2:, physics", "radio 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 2:, physics") OR ("nato science theories 2:, physics"))) OR ("radio science series 2:, physics")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"nato science series 2:, physics\") OR (\"nato science theories 2:, physics\"))) or (\"radio science series 2:, physics\"))".
• Removing quotes may allow a broader search: (((( nato science series 2:, physics ) OR ( nato science theories 2:, physics ))) or ( radio science series 2:, physics )).
• Adding a wildcard symbol may retrieve word variants: (((("nato science series 2:, physics") OR ("nato science theories 2:, physics"))) or ("radio science series 2:, physics"))*.