Perhaps you should try some spelling variations:
"deutsches problem key / history / 18th century" » "deutsche probleme key / history / 18th century", "ethisches problem key / history / 18th century", "deutschland probleme key / history / 18th century", "deutsches problems key / history / 18th century", "deutsches problem k / history / 18th century", "deutsches problem ky / history / 18th century", "deutsches problem k4y / history / 18th century", "deutsches problem keuny / history / 18th century"
"deutsches roten kreuz / history / 18th century" » "deutsches rotes kreuz / history / 18th century", "deutsches patent kreuz / history / 18th century", "deutsches leben kreuz / history / 18th century", "deutsches roten kreuzes / history / 18th century"
"deutschen roten kreuz / history / 18th century" » "deutschen rates kreuz / history / 18th century", "deutschen rechte kreuz / history / 18th century", "deutschen rotes kreuz / history / 18th century", "deutschen roten kreuzes / history / 18th century"
"ethical problem ke / history / 18th century" » "ethical problems ke / history / 18th century", "mechanical problem ke / history / 18th century", "ethische probleme ke / history / 18th century", "ethical problem k / history / 18th century", "ethical problem k4 / history / 18th century", "ethical problem keun / history / 18th century"

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: (((((("deutsches roten kreuz / history / 18th century") OR ("deutschen roten kreuz / history / 18th century"))) OR ("deutsche rote kreuz / history / 18th century"))) OR ((("deutsches problem key / history / 18th century") OR ("ethical problem ke / history / 18th century")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"deutsches roten kreuz / history / 18th century\") OR (\"deutschen roten kreuz / history / 18th century\"))) or (\"deutsche rote kreuz / history / 18th century\"))) or (((\"deutsches problem key / history / 18th century\") or (\"ethical problem ke / history / 18th century\"))))".
• Removing quotes may allow a broader search: (((((( deutsches roten kreuz / history / 18th century ) OR ( deutschen roten kreuz / history / 18th century ))) or ( deutsche rote kreuz / history / 18th century ))) or ((( deutsches problem key / history / 18th century ) or ( ethical problem ke / history / 18th century )))).
• Adding a wildcard symbol may retrieve word variants: (((((("deutsches roten kreuz / history / 18th century") OR ("deutschen roten kreuz / history / 18th century"))) or ("deutsche rote kreuz / history / 18th century"))) or ((("deutsches problem key / history / 18th century") or ("ethical problem ke / history / 18th century"))))*.