Perhaps you should try some spelling variations:
van thanh » van tuan
ban thanh » ban hang
hanh dai » hanh tai, hanh dao, vanh dai
ban hanh » ban hang
duc ban » duc tan, duc van, dua ban
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sai ky » sac ky
tu sai » tu bai, tu san, tu cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sai ky ((nang xa) OR (nang ma)) hoi. thien ((van thanh) or (ban thanh)) duc ban hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky ((nang xa) OR (nang ma)) hoi. thien ((van thanh) OR (ban thanh)) duc ban hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky ((nang xa) OR (nang ma)) hoi. thien ((van thanh) or (ban thanh)) duc ban hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sai ky ((nang xa) OR (nang ma)) hoi. thien ((van thanh) or (ban thanh)) duc ban hanh dai cua tre*.