Perhaps you should try some spelling variations:
va doanh » van doanh, vay doanh, va danh
manh cua » doanh cua, ban cua
mang cua » dung cua, ban cua, cong cua
su sach » so sach, vu sach
hieu ve » hieu van
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
cuu va » cuu van, cuu ve
ma hoi » mai hoi, xa hoi, ma hoa

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 y nang ma hoi. ((hieu va) or (hieu ve)) cap cuu va doanh ((mang cua) OR (manh cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ma hoi. ((hieu va) OR (hieu ve)) cap cuu va doanh ((mang cua) OR (manh cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ma hoi. ((hieu va) or (hieu ve)) cap cuu va doanh ((mang cua) OR (manh cua)) tre*".