Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
nam thuc » nam thuoc, am thuc, nam thu
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
hieu ve » hieu van
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
x hoi » xa hoi, o hoi, x ho

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) or (v nang)) x hoi. ((hieu ve) or (hieu va)) nam thuc van hanh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y nang) OR (v nang)) x hoi. ((hieu ve) OR (hieu va)) nam thuc van hanh vi cua tu.
• Adding a wildcard symbol may retrieve word variants: su sach ((y nang) or (v nang)) x hoi. ((hieu ve) or (hieu va)) nam thuc van hanh vi cua tu*.