Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hoc sach » hoc sinh, hoc cac, hoc anh
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
tang van » dang van, hoang van, trong van
lai cua » dai cua, hai cua, lai chau
duc van » duc va, duc tan, duc manh
cau duc » cao duc, cau luc, chu duc
te sach » toc sach
van cau » van dau, van hau, van chat
van hoc » van hoa
ky tang » ky nang, ky dang, kho tang
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: ((te sach) or (hoc sach)) ky tang van hoc. hieu van cau duc van hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (hoc sach)) ky tang van hoc. hieu van cau duc van hanh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (hoc sach)) ky tang van hoc. hieu van cau duc van hanh lai cua tre*.