Perhaps you should try some spelling variations:
"een internationale seminar prize" » "een international seminar prize" (Expand Search), "een internationaal seminarie prize" (Expand Search), "een internationale meeting prize" (Expand Search), "en internationale seminar prize" (Expand Search), "de internationale seminar prize" (Expand Search), "eerste internationale seminar prize" (Expand Search)
"de international de prize" » "de internationale de prize" (Expand Search), "_ international de prize" (Expand Search), "het internationaal de prize" (Expand Search), "de internationale des prize" (Expand Search), "de international de prijzen" (Expand Search), "de international de prince" (Expand Search), "de international de prijs" (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: (("de international de prize") OR ("een internationale seminar prize"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"de international de prize\") OR (\"een internationale seminar prize\"))*".
• Removing quotes may allow a broader search: (( de international de prize ) OR ( een internationale seminar prize ))*.