Perhaps you should try some spelling variations:
"operateurs de-lineaires / ram" » "operates de-lineaires / ram", "operateurs de-lineare / ram", "operateurs de-linearer / ram", "operateurs de-lineages / ram", "operateurs de-lineaires / raum"
"operations de-linearen / ram" » "operations de-linearen / raum", "operations de-lineare / ram", "operations de-linear / ram"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"operateurs de-lineaires / ram\") OR (\"operations de-linearen / ram\"))".
• Removing quotes may allow a broader search: (( operateurs de-lineaires / ram ) OR ( operations de-linearen / ram )).
• Adding a wildcard symbol may retrieve word variants: (("operateurs de-lineaires / ram") OR ("operations de-linearen / ram"))*.