Perhaps you should try some spelling variations:
instancias » instancia (Expand Search)
academic." » academico." (Expand Search), academia." (Expand Search)
academica." » academicoa." (Expand Search), academiaa." (Expand Search), academico." (Expand Search)
academicos." » academicoos." (Expand Search), academiaos." (Expand Search)
academicoos." » academicooos." (Expand Search), academiaoos." (Expand Search), academico." (Expand Search), academicas." (Expand Search), academics." (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: "(sustancias OR instancias) ((academic." OR academica.") OR (academicos." OR academicoos."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "\"(sustancias OR instancias) ((academic.\" OR academica.\") OR (academicos.\" OR academicoos.\"))".
• Removing quotes may allow a broader search: (sustancias OR instancias) ((academic. OR academica. ) OR (academicos. OR academicoos. )).
• Adding a wildcard symbol may retrieve word variants: "(sustancias OR instancias) ((academic." OR academica.") OR (academicos." OR academicoos."))*.