Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va hanh » va thanh, va danh, ban hanh
sai ky » sac ky
va cau » van cau, va cac, va dau
va cua » va chua, via cua, ca cua

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

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