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