Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
van cham » van chat, van tham, va cham
ve triet » va trien, su triet
thanh di » thanh doi, thanh de, thanh do
ha thanh » va thanh, pham thanh, phan thanh
hieu van » hieu va, thien van, lieu va
thuc ha » thu ha, thuc va, thuc hanh
su sach » so sach, vu sach
ly hang » ly quang
ty hang » ty xang, thi hang, thu hang

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