Perhaps you should try some spelling variations:
ban thanh » ban hanh
sang bao » sang tao, san bao, sang bae
hieu van » hieu va, thien van, lieu va
ban hang » ngan hang
tu sach » thu sach, su sach, te sach
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren
sach ky » sac ky, sach y, sach ty
bao hoa » ba hoa, bao hoc, bao toan
ky sang » ky nang, ky dang, ky tang
van ca » van cau, van cua, dan ca
ca cua » co 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 sang bao hoa. hieu van ca cua ((ban thanh) OR (ban hang)) vai ((cuu tre) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang bao hoa. hieu van ca cua ((ban thanh) OR (ban hang)) vai ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang bao hoa. hieu van ca cua ((ban thanh) OR (ban hang)) vai ((cuu tre) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang bao hoa. hieu van ca cua ((ban thanh) OR (ban hang)) vai ((cuu tre) or (cua tre))*.