Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
va thanh » gia thanh, ban thanh, va tinh
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va danh, ban hanh
y nang » ky nang, ly nang, v nang

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