Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hieu va » lieu va, hieu qua
hai cua » thai cua, dai cua, hoi cua
vai cua » dai cua, lai cua, bai cua
vu sach » vu bach, su sach, vu khach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu van
sach v » sach va, sach y, sach 2
cam tu » cam thu, nam tu, dam tu
tu van » tu va
v nang » va nang, vu nang, van nang

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

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