Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
vien cac » vien bach, vien dai, vien da
nam danh » nam dinh, nam dan
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
xa danh » va danh, dia danh, van danh
sai cua » dai cua, hai cua, lai cua
ve cac » va cac
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky nang x hoi. hieu ((ve cac) or (vien cac)) toc ((xa danh) or (nam danh)) sai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky nang x hoi. hieu ((ve cac) OR (vien cac)) toc ((xa danh) OR (nam danh)) sai cua viet.
• Adding a wildcard symbol may retrieve word variants: doc sach ky nang x hoi. hieu ((ve cac) or (vien cac)) toc ((xa danh) or (nam danh)) sai cua viet*.