Perhaps you should try some spelling variations:
thien van » thi van
danh lai » danh sai, gianh lai, dinh lam
nang cau » nang cao, hang cau, nang dau
chat soc » cham soc, chat doc, chat song
cua viet » hoa viet, cua vat, cua dieu
chat hoc » chat hoa, chat thom, cho hoc
so sach » so sanh, bo sach, co sach
ca viet » va viet, co viet, hoa viet
va danh » va dinh, va dan, va hanh
sach ky » sac ky, sach y, sach ty

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

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