Perhaps you should try some spelling variations:
"complementar contained problem" » "complementar obtained problem" (Expand Search), "complementar contained problema" (Expand Search), "complementar contained problemas" (Expand Search)
"complementaridade constraints problemass" » "complementaridade constraints problemaass" (Expand Search), "complementaridade constraints problemasass" (Expand Search), "complementaridade constraints problemas" (Expand Search), "complementaridade constraints problema" (Expand Search), "complementaridade constraints problems" (Expand Search)

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("complementar contained problem") OR ("complementaridade constraints problemass"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"complementar contained problem\") OR (\"complementaridade constraints problemass\"))".
• Removing quotes may allow a broader search: (( complementar contained problem ) OR ( complementaridade constraints problemass )).
• Adding a wildcard symbol may retrieve word variants: (("complementar contained problem") OR ("complementaridade constraints problemass"))*.