Perhaps you should try some spelling variations:
nam thuoc » nam thu, cay thuoc, va thuoc
nha thuoc » nha nuoc, nhan thuc, nha hoc
nam thuc » am thuc, nam thu, nam tu
vu sach » vu bach, su sach, vu khach
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
vi cua » vai cua, di cua
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: vu sach y nang x hoi. hieu ve ((nam thuc) or (((nam thuoc) OR (nha thuoc)))) va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang x hoi. hieu ve ((nam thuc) OR (((nam thuoc) OR (nha thuoc)))) va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang x hoi. hieu ve ((nam thuc) or (((nam thuoc) OR (nha thuoc)))) va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang x hoi. hieu ve ((nam thuc) or (((nam thuoc) OR (nha thuoc)))) va hanh vi cua tre*.