Perhaps you should try some spelling variations:
"complementaridade constrained problema" » "complementaridade contained problema" (Expand Search), "complementaridade constrained problemas" (Expand Search)
"complementarity constraints problemassssa" » "complementarity constraints problemasssssa" (Expand Search), "complementar constraints problemassssa" (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: (("complementaridade constrained problema") OR ("complementarity constraints problemassssa"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"complementaridade constrained problema\") OR (\"complementarity constraints problemassssa\"))*".
• Removing quotes may allow a broader search: (( complementaridade constrained problema ) OR ( complementarity constraints problemassssa ))*.