Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
hieu van » hieu va, thien van, lieu va
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
van lam » van nam
qua ban » qua quan
cua tre » cua te, cuu tre, cua triet
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang ma) or (sang ma)) hoa. hieu van lam ((cua ban) or (qua ban)) thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang ma) OR (sang ma)) hoa. hieu van lam ((cua ban) OR (qua ban)) thanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang ma) or (sang ma)) hoa. hieu van lam ((cua ban) or (qua ban)) thanh dai cua tre*.