Perhaps you should try some spelling variations:
va trien » va truyen, va thiet, va tuyen
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
chat huu » pham huu
sach ly » sach y, sach lo, sach ty
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 va » bi va, gi la, gi ta

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) OR (ban hanh)) gi va trien~.
• 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) OR (ban hanh)) gi va trien.
• 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) OR (ban hanh)) gi va trien".
• Adding a wildcard symbol may retrieve word variants: tu sach ly nang xa hoi. ((hieu vu) or (hieu va)) chat huu ((van hanh) OR (ban hanh)) gi va trien*.