Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
vinh cuu » dinh cuu, sinh cua, dinh cu
tu sach » thu sach, su sach, te sach
qua dao » lua dao, qua da, cua dao
dao tuc » dao duc
tuc van » thuc van, truc van, tuc va
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
vi cuu » vi luu
x hoi » o hoi, x ho, 5 hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach v nang ((x hoi) OR (xa hoi)). hieu qua dao tuc van hanh ((vi cuu) OR (vinh cuu)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach v nang ((x hoi) or (xa hoi)). hieu qua dao tuc van hanh ((vi cuu) OR (vinh cuu)) tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach v nang ((x hoi) or (xa hoi)). hieu qua dao tuc van hanh ((vi cuu) OR (vinh cuu)) tre*.