Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
dai cuu » dai cua, dai huu
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
qua cau » quan cau, qua cac, qua ca
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach tu, sach thu
sach xa » sach dao, sach nha, sach bai
cuu tre » cua tre, cau tren, cau treo

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 ty) or (sach xa)) ((nang x) or (nang ma)) hoi. hieu qua cau truc va hanh dai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach xa)) ((nang x) OR (nang ma)) hoi. hieu qua cau truc va hanh dai cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach xa)) ((nang x) or (nang ma)) hoi. hieu qua cau truc va hanh dai cuu tre*.