Perhaps you should try some spelling variations:
ihrer grenzgebiete » ihren grenzgebieten, der grenzgebiete, deren grenzgebiete
ihre grenzgebiete » ihren grenzgebieten, die grenzgebiete, im grenzgebiet
modern survey » modern surgery, model survey, modeling survey
models survey » modeling survey, models supply
other surveys » other survey, other surgeons
oder surveys » der surveys, cover surveys, user surveys
2c a » 12c a, 2 a, c a

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: %ergebnisse der mathematik und ((ihrer grenzgebiete) OR (ihre grenzgebiete)). 2. folge%2c a series of ((((modern survey) OR (models survey))) OR (((oder surveys) OR (other surveys)))) in mathematics%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%ergebnisse der mathematik und ((ihrer grenzgebiete) or (ihre grenzgebiete)). 2. folge%2c a series of ((((modern survey) OR (models survey))) or (((oder surveys) or (other surveys)))) in mathematics%22".
• Adding a wildcard symbol may retrieve word variants: %ergebnisse der mathematik und ((ihrer grenzgebiete) or (ihre grenzgebiete)). 2. folge%2c a series of ((((modern survey) OR (models survey))) or (((oder surveys) or (other surveys)))) in mathematics%22*.