Perhaps you should try some spelling variations:
"complementarity obtained problem" » "complementaridade obtained problem" (Expand Search), "complementarity obtained problema" (Expand Search), "complementarity obtained problemas" (Expand Search)
"complementar constraints problemaaasa" » "complementar constraints problemaaaasa" (Expand Search), "complementar constraints problemasaaasa" (Expand Search), "complementar constraints problemas" (Expand Search), "complementar constraints problematica" (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: (("complementarity obtained problem") OR ("complementar constraints problemaaasa"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"complementarity obtained problem\") OR (\"complementar constraints problemaaasa\"))".
• Removing quotes may allow a broader search: (( complementarity obtained problem ) OR ( complementar constraints problemaaasa )).
• Adding a wildcard symbol may retrieve word variants: (("complementarity obtained problem") OR ("complementar constraints problemaaasa"))*.