Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
vai cua » dai cua, hai cua, lai cua
qua ban » cua ban, qua quan
cam qua » cau qua, cac qua, cay qua
van cam » van nam, van lam, van cau
sach ky » sac ky, sach kem, sach hay
nang ma » tang ma, sang ma, nang cao
sach ty » sach tu, sach thu, xach tay
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ky) or (((sach ty) OR (sach y)))) nang ma hoi. hieu van cam qua ban thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (((sach ty) OR (sach y)))) nang ma hoi. hieu van cam qua ban thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) or (((sach ty) OR (sach y)))) nang ma hoi. hieu van cam qua ban thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (((sach ty) OR (sach y)))) nang ma hoi. hieu van cam qua ban thanh vai cua tre*.