Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
van cam » van nam, van lam, van cau
va hanh » va thanh, va danh, ban hanh
cuc te » cua te, cuc thue, cuc tieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ky ((nang xa) or (nang x)) hoi. hieu van cam xuc ((va hanh) OR (van hanh)) tai cuc te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky ((nang xa) OR (nang x)) hoi. hieu van cam xuc ((va hanh) OR (van hanh)) tai cuc te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ky ((nang xa) or (nang x)) hoi. hieu van cam xuc ((va hanh) OR (van hanh)) tai cuc te".
• Adding a wildcard symbol may retrieve word variants: hoc sach ky ((nang xa) or (nang x)) hoi. hieu van cam xuc ((va hanh) OR (van hanh)) tai cuc te*.