Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
thanh di » thanh doi, thanh de, thanh do
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
cuu tre » cua tre, cau tren
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
nam xuc » cam xuc, nam xua, nam thuc
xuc va » duc va, tuc va, luc va
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 ky) or (sach ty)) nang x hoi. hieu van nam xuc va thanh di ((cuu tre) OR (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach ty)) nang x hoi. hieu van nam xuc va thanh di ((cuu tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) or (sach ty)) nang x hoi. hieu van nam xuc va thanh di ((cuu tre) OR (cau treo))".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sach ty)) nang x hoi. hieu van nam xuc va thanh di ((cuu tre) OR (cau treo))*.