Perhaps you should try some spelling variations:
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
tu sach » thu sach, te sach, tu cach
hieu va » lieu va, hieu qua
vu nang » vuc nang, va nang, vu dang
su sach » so sach, vu sach
su hien » su kien, su tien, thu hien
x hoi » xa hoi, o hoi, x ho
ve su » va su

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) OR (su sach)) vu nang x hoi. hieu va cac nuoc ((van hanh) OR (ban hanh)) ve su hien~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) vu nang x hoi. hieu va cac nuoc ((van hanh) or (ban hanh)) ve su hien~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) vu nang x hoi. hieu va cac nuoc ((van hanh) or (ban hanh)) ve su hien*.