Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
lam duoc » nam duoc, luat duoc, lam thuoc
kinh lai » kinh hai, minh lai, tinh lai
ty hang » ly hang, thi hang, thu hang
van lam » van nam
duoc va » nuoc va, duc va, duoc ma
va kinh » va tinh, qua kinh
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ty xang) or (ty hang)) xa hoi. hieu van lam duoc va kinh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ty xang) OR (ty hang)) xa hoi. hieu van lam duoc va kinh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ty xang) or (ty hang)) xa hoi. hieu van lam duoc va kinh lai cua tre*.