Perhaps you should try some spelling variations:
les recherches » des recherches, de recherches
recherches sur » recherche sur
progres dans » progres de
pre cancer » care cancer
le cancer » e cancer, male cancer

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: recent results in cancer research, fortschritte der krebsforschung ((progres dans) OR (progres des)) les recherches sur ((le cancer) OR (pre cancer)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "recent results in cancer research, fortschritte der krebsforschung ((progres dans) OR (progres des)) les recherches sur ((le cancer) or (pre cancer))".
• Adding a wildcard symbol may retrieve word variants: recent results in cancer research, fortschritte der krebsforschung ((progres dans) OR (progres des)) les recherches sur ((le cancer) or (pre cancer))*.