Perhaps you should try some spelling variations:
co sach » bo sach, cuon sach, hoc sach
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
hieu ly » hieu ky, lieu ly, dieu ly
nang ma » tang ma, sang ma, nang cao
hieu le » hieu ve, hieu he, tieu le
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
vi cuu » vi luu, vinh cuu
nuoc » quoc, duoc, ngoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach y nang ma hoi. ((hieu le) or (hieu ly)) dat nuoc ((va hanh) or (va danh)) vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach y nang ma hoi. ((hieu le) OR (hieu ly)) dat nuoc ((va hanh) OR (va danh)) vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: co sach y nang ma hoi. ((hieu le) or (hieu ly)) dat nuoc ((va hanh) or (va danh)) vi cuu tre*.