Perhaps you should try some spelling variations:
"dynamisches system" » "dynamischer systeme", "dynamische systeme", "dynamical system"
"economic systems" » "economic sectors"
"dynamics system" » "dynamic system", "dynamical system", "dynamical systems"
"dynamic systems" » "dynamical systems"

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: (((("dynamics system") OR ("dynamisches system"))) OR ((("dynamic systems") OR ("economic systems")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"dynamics system\") OR (\"dynamisches system\"))) or (((\"dynamic systems\") or (\"economic systems\"))))".
• Removing quotes may allow a broader search: (((( dynamics system ) OR ( dynamisches system ))) or ((( dynamic systems ) or ( economic systems )))).
• Adding a wildcard symbol may retrieve word variants: (((("dynamics system") OR ("dynamisches system"))) or ((("dynamic systems") or ("economic systems"))))*.