Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
ve triet » va trien, su triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
va cao » va cac, va dao, va bao
va co » vo co
va ve » va de, va le, va vi

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 mai hoi. hieu ((va cao) OR (va co)) tu ((va hanh) or (va danh)) va ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang mai hoi. hieu ((va cao) OR (va co)) tu ((va hanh) OR (va danh)) va ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang mai hoi. hieu ((va cao) OR (va co)) tu ((va hanh) or (va danh)) va ve triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang mai hoi. hieu ((va cao) OR (va co)) tu ((va hanh) or (va danh)) va ve triet*.