Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
tu sach » thu sach, su sach, te sach
ky sang » ky nang, ky dang, duy sang
ky tang » ky nang, ky dang, kho tang
hieu va » lieu va, hieu qua
qua ban » cua ban, qua quan
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua
va cau » van cau, va cac, va dau

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) OR (ky tang)) ma hoa. hieu va cau qua ban thanh ((vai cua) or (hai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky sang) OR (ky tang)) ma hoa. hieu va cau qua ban thanh ((vai cua) OR (hai cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky sang) OR (ky tang)) ma hoa. hieu va cau qua ban thanh ((vai cua) or (hai cua)) tre*".