Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
danh dai » danh dau, danh sai, vanh dai
van chat » cao chat
chat soc » cham soc, chat hoc, chat doc
ky lang » ky dang, ky tang, tay lang
danh di » danh du, xanh di, danh dien
tu sach » thu sach, su sach, te sach
soc va » hoc va, loc va, doc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky lang) OR (ky nang)) xa hoi. hieu van chat soc va ((danh dai) or (danh di)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky nang)) xa hoi. hieu van chat soc va ((danh dai) OR (danh di)) cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) OR (ky nang)) xa hoi. hieu van chat soc va ((danh dai) or (danh di)) cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) OR (ky nang)) xa hoi. hieu van chat soc va ((danh dai) or (danh di)) cua viet*.