Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
te sach » toc sach
dai cuu » dai cua, dai huu
cac dac » cac dan, cac dai, cac bac
cac duc » cac du, cao duc, cac nuoc
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y ((nang ma) OR (tang ma)) hoi. hieu ve ((cac duc) or (cac dac)) gia thanh dai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang ma) OR (tang ma)) hoi. hieu ve ((cac duc) OR (cac dac)) gia thanh dai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang ma) OR (tang ma)) hoi. hieu ve ((cac duc) or (cac dac)) gia thanh dai cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang ma) OR (tang ma)) hoi. hieu ve ((cac duc) or (cac dac)) gia thanh dai cuu tre*.