Perhaps you should try some spelling variations:
va tuyen » va truyen, tac tuyen, ke tuyen
nam truc » nam truoc, nam thuc, nam trung
va trien » va truyen, va thiet, va tieng
cam truc » cau truc, lam truoc, nam truoc
va hanh » van hanh, va thanh, va danh
co sach » bo sach, cuon sach, hoc sach
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: co sach y nang ma hoi. hieu qua ((cam truc) OR (nam truc)) va hanh vi ((va trien) OR (va tuyen))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach y nang ma hoi. hieu qua ((cam truc) or (nam truc)) va hanh vi ((va trien) OR (va tuyen))~".
• Adding a wildcard symbol may retrieve word variants: co sach y nang ma hoi. hieu qua ((cam truc) or (nam truc)) va hanh vi ((va trien) OR (va tuyen))*.