Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
ban hanh » ban hang
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
tu nong » tu dong, tu cong, tu tong
cac xuc » cam xuc, cac nuoc, chat xuc
va hanh » van hanh, va thanh, va danh
nong o » nong do, nong co, dong o
su cao » cu cao, vu cao, su co
vi cua » vai cua, di cua
su can » su van, tu can, su han
o hoi » co hoi, o hoc, o hai

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((su can) OR (su cao)) tu nong o hoi. hieu van cac xuc ((va hanh) or (ban hanh)) vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su can) OR (su cao)) tu nong o hoi. hieu van cac xuc ((va hanh) OR (ban hanh)) vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su can) OR (su cao)) tu nong o hoi. hieu van cac xuc ((va hanh) or (ban hanh)) vi cua viet".
• Adding a wildcard symbol may retrieve word variants: ((su can) OR (su cao)) tu nong o hoi. hieu van cac xuc ((va hanh) or (ban hanh)) vi cua viet*.