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"

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 ("dynamical systems"))) 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 (\"dynamical systems\"))) or (((\"dynamic systems\") or (\"economic systems\"))))".
• Removing quotes may allow a broader search: (((((( dynamics system ) OR ( dynamisches system ))) or ( dynamical systems ))) or ((( dynamic systems ) or ( economic systems )))).
• Adding a wildcard symbol may retrieve word variants: (((((("dynamics system") OR ("dynamisches system"))) or ("dynamical systems"))) or ((("dynamic systems") or ("economic systems"))))*.