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