Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
chat huu » pham huu
sach ly » sach y, sach lo, sach ty
huu van » cuu van, huu han, luu van
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
hieu vu » hieu ve, hieu su, dieu vu
nang xa » nang x, lang xa, nang ma
ly nang » ky nang, ly hang, ly vang
gi ve » gia ve, gi de, vi ve
gi he » gi de, vi he

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