Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thanh di » thanh doi, thanh de, thanh do
thuc ban » thuoc ban, thuc dan, thu ban
thu hang » thi hang, thuc hanh, thu huong
van pham » san pham, van phan, van phat
so sach » so sanh, bo sach, co sach
ly hang » ly quang
ty hang » ty xang, thi hang
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: so sach ((((ty hang) OR (thu 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: so sach ((((ty hang) OR (thu hang))) OR (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((((ty hang) OR (thu hang))) or (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach ((((ty hang) OR (thu hang))) or (ly hang)) xa hoi. hieu van pham thuc ban thanh di cua tre*.