Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
va thanh » gia thanh, ban thanh, le thanh
sach ky » sac ky, sach y, sach ty
va tinh » may tinh
su sach » so sach, vu sach
va hanh » van hanh, va danh, ban hanh
hieu te » hieu ve, hien te, hieu he
ban co » ban do, san co
te ban » te bao
vi cau » va cau, ve cau, di cau
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 ky nang x hoi. hieu te ban co ((va hanh) or (((va thanh) OR (va tinh)))) vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. hieu te ban co ((va hanh) OR (((va thanh) OR (va tinh)))) vi cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. hieu te ban co ((va hanh) or (((va thanh) OR (va tinh)))) vi cau tren".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu te ban co ((va hanh) or (((va thanh) OR (va tinh)))) vi cau tren*.