Perhaps you should try some spelling variations:
ihrer grenzgebiete » ihren grenzgebieten, der grenzgebiete, deren grenzgebiete
mathematical user » mathematics user, mathematical using, esomathematical uses
ihre grenzgebiete » ihren grenzgebieten, die grenzgebiete, im grenzgebiet
mathematical und » mathematica und, mathematical union, mathematical using
modest survey » model survey, modern survey, codes survey
models survey » modeling survey, models supply

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