Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
pham thuc » phap thuc, pham chuc, nham thuc
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
thuc ban » thuoc ban, thuc dan, thu ban
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
ty hang » ty xang, thi hang, thu hang
ly hang » ly quang
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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 hang) or (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty hang) OR (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ((ty hang) or (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre*.