Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh tai
ban hanh » ban hang
cuu tre » cua tre, cau treo
dua ban » dia ban, cua ban, qua ban
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
bao hoa » ba hoa, bao hoc, bao toan
tao hoa » tao hoi, tao ho, tao hop
ky sang » ky nang, ky dang, ky tang
ca dua » cay dua, ca cua, ca da
van ca » van cau, van cua, dan ca

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 ((tao hoa) or (bao hoa)). hieu van ca dua ban hanh vai ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ((tao hoa) OR (bao hoa)). hieu van ca dua ban hanh vai ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang ((tao hoa) or (bao hoa)). hieu van ca dua ban hanh vai ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ((tao hoa) or (bao hoa)). hieu van ca dua ban hanh vai ((cuu tre) OR (cau tren))*.