Perhaps you should try some spelling variations:
ngang duoc » nganh duoc, nhan duoc
tu ngang » tu ngan, hu angang, vu ngan
duoc hoi » quoc hoi, duoc hoc, duoc si
hieu van » hieu va, thien van, hieu ve
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
nam luc » nang luc, nhan luc, nam thuc
sach tu » sach thu, cach tu, sach ty
luc va » duc va, tuc va, loc va
va cau » van cau, va cac, va cao
va dau » va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach tu ngang duoc hoi. ((hieu van) or (lieu va)) nam luc va hanh ((va cau) OR (va dau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu ngang duoc hoi. ((hieu van) OR (lieu va)) nam luc va hanh ((va cau) OR (va dau)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tu ngang duoc hoi. ((hieu van) or (lieu va)) nam luc va hanh ((va cau) OR (va dau)) tren".
• Adding a wildcard symbol may retrieve word variants: tu sach tu ngang duoc hoi. ((hieu van) or (lieu va)) nam luc va hanh ((va cau) OR (va dau)) tren*.