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