Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cau tren » cu tren, dau tren, cau treo
dinh vai » dinh van, dinh vi, dinh va
va dinh » van dinh, va kinh, va tinh
van cam » van nam, van lam, van cau
lai hoi » dai hoi, lai hoa, lai roi
ky tang » ky nang, ky dang, kho tang
ky sang » ky nang, ky dang, duy sang
ca tren » cu tren, la tren, co tren
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ky sang) or (ky tang)) lai hoi. hieu van cam xuc va dinh vai ((cau tren) or (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky sang) OR (ky tang)) lai hoi. hieu van cam xuc va dinh vai ((cau tren) OR (ca tren)).
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky sang) or (ky tang)) lai hoi. hieu van cam xuc va dinh vai ((cau tren) or (ca tren))*.