Perhaps you should try some spelling variations:
krebsforschung progres » krebsforschung from
recherches sur » recherche sur
pre cancer » care cancer
le cancer » male cancer
de leurs » de leur

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 ((de les) OR (de leurs)) recherches sur ((((le cancer) OR (e 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 ((de les) OR (de leurs)) recherches sur ((((le cancer) or (e cancer))) or (pre cancer))".
• Adding a wildcard symbol may retrieve word variants: recent results in cancer research, fortschritte der krebsforschung progres ((de les) OR (de leurs)) recherches sur ((((le cancer) or (e cancer))) or (pre cancer))*.