Perhaps you should try some spelling variations:
delta letteratura » della letteratura, nella letteratura, diventa letteratura
letteratura arte » letteratura arti, letteratura sarda, letteratura e
letteratura di » letteratura e, literatura de
pair delta » bar delta, pair data, ppar delta
i ground » i group, i groups, i grand

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: (( ((i ground) OR (i grunde)) pair delta letteratura di ) OR ( ((i ground) OR (i grunde))s livre _ letteratura arte )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((i ground) OR (i grunde)) pair delta letteratura di ) or ( ((i ground) OR (i grunde))s livre _ letteratura arte ))".
• Adding a wildcard symbol may retrieve word variants: (( ((i ground) OR (i grunde)) pair delta letteratura di ) or ( ((i ground) OR (i grunde))s livre _ letteratura arte ))*.