Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vi » hanh vi, thanh va, thanh ve
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
van bac » van ban, van bao, dan bac
van hac » van hoc, van ha, van hai
dat ban » bat ban, da ban, day ban
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: tu sach ky nang ((ma hoa) or (mai hoi)). hieu ((van bac) OR (van hac)) dat ban thanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((ma hoa) OR (mai hoi)). hieu ((van bac) OR (van hac)) dat ban thanh vi cua vat*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((ma hoa) or (mai hoi)). hieu ((van bac) OR (van hac)) dat ban thanh vi cua vat*".