Perhaps you should try some spelling variations:
ihre grenzgebiete » ihren grenzgebieten, die grenzgebiete, im grenzgebiet
user surveys » use surveys, user survey, cluster surveys
deep surveys » deep survey, best surveys
der surveys » ir surveys, nir surveys, other surveys

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