Perhaps you should try some spelling variations:
internationale seminar » international seminar (Expand Search), internationaal seminarie (Expand Search), internationale meeting (Expand Search)
en internationale » de internationale (Expand Search), _ international (Expand Search), het internationaal (Expand Search)
et internationale » een internationale (Expand Search), de internationale (Expand Search), het internationaal (Expand Search)
de prize » de prince (Expand Search), de prijs (Expand Search), de prins (Expand Search)

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: "(( en internationale ((de prize) OR (de prijzen)) ) OR ( et internationale seminar prize ))~".
• Adding a wildcard symbol may retrieve word variants: (( en internationale ((de prize) OR (de prijzen)) ) OR ( et internationale seminar prize ))*.