Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh di » thanh doi, thanh de, thanh do
va thanh » gia thanh, ban thanh, va tinh
cua tre » cua te, cua triet, dua tren
sach ty » sach y, sach tu, sach thu
van cam » van nam, van lam, van cau
cuu tre » cau tren, cau treo
cam tu » cam thu, nam tu, dam tu
sai ky » sac ky
x hoi » xa hoi, o hoi, x ho

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 ty) or (sai ky)) nang x hoi. hieu van cam tu va thanh di ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sai ky)) nang x hoi. hieu van cam tu va thanh di ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sai ky)) nang x hoi. hieu van cam tu va thanh di ((cua tre) or (cuu tre))*.