Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam tu
hanh lai » hanh lam, hanh tai, thanh lap
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky sang » ky nang, ky dang, ky tang
xa hanh » xa thanh, xa khanh, va hanh
lai cua » dai cua, hai cua, lai chau
ma hoi » mai hoi, ma hoa, me hoi
cua te » cua tu

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 sang ((ma hoi) or (xa hoi)). hieu van ((nam thuc) OR (nam thu)) xa hanh lai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ((ma hoi) OR (xa hoi)). hieu van ((nam thuc) OR (nam thu)) xa hanh lai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang ((ma hoi) or (xa hoi)). hieu van ((nam thuc) OR (nam thu)) xa hanh lai cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ((ma hoi) or (xa hoi)). hieu van ((nam thuc) OR (nam thu)) xa hanh lai cua te*.