Perhaps you should try some spelling variations:
ban doanh » van doanh, san doanh, toan doanh
su triet » su viet, su tien, ve triet
ban danh » ban hanh, ban dan, van danh
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
tu sach » thu sach, su sach, te sach
ca cua » co cua
ve ca » ve cac, ve cai, ve cau

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 xa hoi. hieu ve ca cua ((ban danh) OR (ban doanh)) vai ((cua tre) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. hieu ve ca cua ((ban danh) OR (ban doanh)) vai ((cua tre) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang xa hoi. hieu ve ca cua ((ban danh) OR (ban doanh)) vai ((cua tre) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu ve ca cua ((ban danh) OR (ban doanh)) vai ((cua tre) or (su triet))*.