Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
truc va » thuc va, trung va
y lang » o lang, tay lang, yen lang
_ lang » o lang, _ land
ve cam » ve cham, ve cac, va cam
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((y lang) OR (_ lang)) xa hoi. hieu ve cam ((truc va) or (thuc vat)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y lang) OR (_ lang)) xa hoi. hieu ve cam ((truc va) OR (thuc vat)) hanh vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y lang) OR (_ lang)) xa hoi. hieu ve cam ((truc va) or (thuc vat)) hanh vi cua viet".
• Adding a wildcard symbol may retrieve word variants: su sach ((y lang) OR (_ lang)) xa hoi. hieu ve cam ((truc va) or (thuc vat)) hanh vi cua viet*.