Perhaps you should try some spelling variations:
van triet » va triet, van thiet, van trieu
nam thuc » nam thuoc, am thuc, nam thu
dang xay » dang van, van xay
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
dam thuc » am thuc, dan thuc, dai thuc
va hanh » van hanh, va danh, ban hanh
so sach » so sanh, bo sach, co sach
xay hoi » xa hoi, tay hoi, cay phoi
sach 2 » sach y
2 dang » 2 danh, _ dang, b dang

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 2 dang xay hoi. hieu van ((dam thuc) or (nam thuc)) ((va hanh) OR (va thanh)) vi van triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach 2 dang xay hoi. hieu van ((dam thuc) OR (nam thuc)) ((va hanh) OR (va thanh)) vi van triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach 2 dang xay hoi. hieu van ((dam thuc) or (nam thuc)) ((va hanh) OR (va thanh)) vi van triet*".