Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
hieu le » hieu ve, hieu he, hieu ly
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho
le am » le ham, le nam, le a
thuc » thu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu bach)) y nang x hoi. hieu le am thuc vat thanh di ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu bach)) y nang x hoi. hieu le am thuc vat thanh di ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu bach)) y nang x hoi. hieu le am thuc vat thanh di ((cua tre) or (cuu tre))*.