Perhaps you should try some spelling variations:
protests during » process during, processes during, products during
der filosofica » de filosofia, e filosofica, e filosofia
la literatura » la litterature
studies der » studies ds, studies d, studies dn

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((protests during) OR (proteins during)) studies der filosofica ((la literatura) OR (a literature)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((protests during) or (proteins during)) studies der filosofica ((la literatura) OR (a literature))".
• Adding a wildcard symbol may retrieve word variants: ((protests during) or (proteins during)) studies der filosofica ((la literatura) OR (a literature))*.