Perhaps you should try some spelling variations:
heilkunde 1991 » heilkunde 11, heilkunde 15.15, heilkunde 10
heilkunde 1 » heilkunde 10, heilkunde 11, heilkunde 16
verh.bern.dt.gold.hno- » very.bern.dt.gold.hno-, ver.bern.dt.gold.hno-, verb.bern.dt.gold.hno-, verh.born.dt.gold.hno-, verh.ben.dt.gold.hno-, verh.bern.dt.good.hno-, verh.bern.dt.god.hno-
vers.been.dt.geld.hno-heilkunde » verse.been.dt.geld.hno-heilkunde, verso.been.dt.geld.hno-heilkunde, very.been.dt.geld.hno-heilkunde
vers.been.dt.gel.hno-heilkunde » verse.been.dt.gel.hno-heilkunde, verso.been.dt.gel.hno-heilkunde, very.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.gold.hno-((heilkunde 1991) OR (heilkunde 1)) ) OR ( (vers.been.dt.geld.hno-heilkunde OR vers.been.dt.gel.hno-heilkunde) 1991 )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( verh.bern.dt.gold.hno-((heilkunde 1991) OR (heilkunde 1)) ) or ( (vers.been.dt.geld.hno-heilkunde or vers.been.dt.gel.hno-heilkunde) 1991 ))".
• Adding a wildcard symbol may retrieve word variants: (( verh.bern.dt.gold.hno-((heilkunde 1991) OR (heilkunde 1)) ) or ( (vers.been.dt.geld.hno-heilkunde or vers.been.dt.gel.hno-heilkunde) 1991 ))*.