Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
hieu ve » hieu va
sach ty » sach y, sach tu, sach thu
duc van » duc va, duc tan, duc manh
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
lai cua » dai cua, lai chau, thai cua
hai cua » thai cua, dai cua, hoi cua
tu sach » thu sach, su sach, te sach

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 nang xa hoi. ((hieu ve) OR (hieu van)) pham duc van hanh ((lai cua) or (hai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) pham duc van hanh ((lai cua) OR (hai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) pham duc van hanh ((lai cua) or (hai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) pham duc van hanh ((lai cua) or (hai cua)) triet*.