Perhaps you should try some spelling variations:
"nato asi subseries f:, computer and system sciences" » "nato asi subseries f:, computer and systems sciences", "nato asi subseries a:, computer and system sciences", "nato asi substrates f:, computer and system sciences", "nato arw subseries f:, computer and system sciences"
"nato _ subseries f:, computer and system sciences" » "nato _ subseries f:, computer and systems sciences", "nato _ subseries a:, computer and system sciences", "nato _ substrates f:, computer and system sciences"
"nato _ subseries f:, computer and system science" » "nato _ subseries f:, computer and systems science", "nato _ subseries a:, computer and system science", "nato _ substrates f:, computer and system science"

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 asi subseries f:, computer and system sciences") OR ((("nato _ subseries f:, computer and system sciences") OR ("nato _ subseries f:, computer and system science")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"nato asi subseries f:, computer and system sciences\") or (((\"nato _ subseries f:, computer and system sciences\") OR (\"nato _ subseries f:, computer and system science\"))))".
• Removing quotes may allow a broader search: (( nato asi subseries f:, computer and system sciences ) or ((( nato _ subseries f:, computer and system sciences ) OR ( nato _ subseries f:, computer and system science )))).
• Adding a wildcard symbol may retrieve word variants: (("nato asi subseries f:, computer and system sciences") or ((("nato _ subseries f:, computer and system sciences") OR ("nato _ subseries f:, computer and system science"))))*.