Perhaps you should try some spelling variations:
"de internationale seminar prize" » "de international seminar prize" (Expand Search), "de internationaal seminarie prize" (Expand Search), "de internationale meeting prize" (Expand Search), "_ international seminar prize" (Expand Search), "_ internationale seminar prize" (Expand Search), "het internationaale seminar prize" (Expand Search), "en internationalee seminar prize" (Expand Search)
"de international de prijzen" » "_ international de prijzen" (Expand Search), "het internationaal de prijzen" (Expand Search), "en internationale de prijzen" (Expand Search), "de internationale des prijzen" (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: "((\"de international de prijzen\") OR (\"de internationale seminar prize\"))~".
• Removing quotes may allow a broader search: (( de international de prijzen ) OR ( de internationale seminar prize ))~.
• Adding a wildcard symbol may retrieve word variants: (("de international de prijzen") OR ("de internationale seminar prize"))*.