Perhaps you should try some spelling variations:
heilkunde 15.15 » heilkunde 5.1, heilkunde 11
heilkunde 1991 » heilkunde 11, heilkunde 1, heilkunde 10
verh.bern.dt.geld.hno-heilkunde » very.bern.dt.geld.hno-heilkunde, ver.bern.dt.geld.hno-heilkunde, verb.bern.dt.geld.hno-heilkunde, verh.ben.dt.geld.hno-heilkunde, verh.bern.dt.gold.hno-heilkunde
vers.born.dt.gel.hno-heilkunde » verso.born.dt.gel.hno-heilkunde, very.born.dt.gel.hno-heilkunde, ver.born.dt.gel.hno-heilkunde
verse.born.dt.gel.hno-heilkunde » versoe.born.dt.gel.hno-heilkunde, verye.born.dt.gel.hno-heilkunde, vere.born.dt.gel.hno-heilkunde
vers.been.dt.gel.hno-heilkunde » verso.been.dt.gel.hno-heilkunde, very.been.dt.gel.hno-heilkunde, ver.been.dt.gel.hno-heilkunde

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: (( verh.bern.dt.geld.hno-heilkunde 1991 ) OR ((( (vers.born.dt.gel.hno-heilkunde OR verse.born.dt.gel.hno-heilkunde) 10 ) OR ( vers.been.dt.gel.hno-heilkunde 15.15 )))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( verh.bern.dt.geld.hno-heilkunde 1991 ) or ((( (vers.born.dt.gel.hno-heilkunde OR verse.born.dt.gel.hno-heilkunde) 10 ) or ( vers.been.dt.gel.hno-heilkunde 15.15 ))))".
• Adding a wildcard symbol may retrieve word variants: (( verh.bern.dt.geld.hno-heilkunde 1991 ) or ((( (vers.born.dt.gel.hno-heilkunde OR verse.born.dt.gel.hno-heilkunde) 10 ) or ( vers.been.dt.gel.hno-heilkunde 15.15 ))))*.