Perhaps you should try some spelling variations:
"internationale conferentie opposition" » "international conference opposition" (Expand Search)
"internationale de opposition" » "international de opposition" (Expand Search), "internationale de l'opposition" (Expand Search), "internationale d'ete opposition" (Expand Search)
"internationale des propositions" » "international des propositions" (Expand Search)
"international des propositions" » "international de propositions" (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("internationale de opposition") OR ("internationale conferentie opposition"))) OR ((("internationale des propositions") OR ("international des propositions"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"internationale de opposition\") OR (\"internationale conferentie opposition\"))) OR (((\"internationale des propositions\") OR (\"international des propositions\"))))".
• Removing quotes may allow a broader search: (((( internationale de opposition ) OR ( internationale conferentie opposition ))) OR ((( internationale des propositions ) OR ( international des propositions )))).
• Adding a wildcard symbol may retrieve word variants: (((("internationale de opposition") OR ("internationale conferentie opposition"))) OR ((("internationale des propositions") OR ("international des propositions"))))*.