Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van chay » van chat, san chay, toan chay
thu sach » thuat sach, thuoc sach, thu hoach
hanh vai » hanh vi, hanh va, hanh tai
ban hanh » ban hang
cua tre » cuu tre, cua triet, dua tren
dua ban » dia ban, cua ban, qua ban
tu sach » su sach, te sach, tu cach
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
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) OR (thu sach)) ky tang ma hoa. hieu van chay dua ban hanh vai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky tang ma hoa. hieu van chay dua ban hanh vai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky tang ma hoa. hieu van chay dua ban hanh vai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky tang ma hoa. hieu van chay dua ban hanh vai ((cua tre) or (cua te))*.