Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh vi » hanh vi, thanh va, thanh ve
hieu van » hieu va, thien van, lieu va
cau treo » cau theo, cau tren, cau triet
lang xa » lang ha, dang xay, lang van
van cam » van nam, van lam, van cau
sach ky » sac ky, sach ty, sach kem
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
cam duc » cam xuc, cao duc, pham duc

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

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