Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
luc van » luoc van, luu van, duc van
vai cua » dai cua, hai cua, lai cua
y nang » ky nang, ly nang, v nang
qua ca » qua cac, qua cua, qua cai
ca luc » cau luc, ca lua
de cua » le cua, te cua, dieu cua
x hoi » xa hoi, o hoi, x ho

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 x hoi. hieu qua ca luc van hanh ((vai cua) or (de cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang x hoi. hieu qua ca luc van hanh ((vai cua) OR (de cua)) tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x hoi. hieu qua ca luc van hanh ((vai cua) or (de cua)) tre*.