Perhaps you should try some spelling variations:
der mathematical » her mathematical, mer mathematical, order mathematical
models survey » modeling survey, models supply
model survey » model surgery, modern survey, moral survey
und ihrer » und ihr

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: ergebnisse der mathematical ((und ihrer) OR (und ihre)) grenzgebiete. 2. folge, a series of ((model survey) OR (models survey)) in mathematics.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ergebnisse der mathematical ((und ihrer) OR (und ihre)) grenzgebiete. 2. folge, a series of ((model survey) or (models survey)) in mathematics".
• Adding a wildcard symbol may retrieve word variants: ergebnisse der mathematical ((und ihrer) OR (und ihre)) grenzgebiete. 2. folge, a series of ((model survey) or (models survey)) in mathematics*.