Perhaps you should try some spelling variations:
"informatik modelle" » "informatik modell", "information modelle", "geoinformatik modelle"
"informative model" » "informative models", "information model", "normative model"
"informatic model" » "informatic models", "information model", "informatik modell"

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: (((("informatic model") OR ("informative model"))) OR ("informatik modelle")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"informatic model\") OR (\"informative model\"))) or (\"informatik modelle\"))".
• Removing quotes may allow a broader search: (((( informatic model ) OR ( informative model ))) or ( informatik modelle )).
• Adding a wildcard symbol may retrieve word variants: (((("informatic model") OR ("informative model"))) or ("informatik modelle"))*.