Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
dang xay » dang van, van xay
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
cac luc » cau luc, coc luc, cac nuoc
vu sach » vu bach, vu khach
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh
su sach » so sach
cua tre » cua te, cuu tre, cua triet
luc va » duc va, tuc va, loc va
va cua » va chua, via cua, ca cua

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) or (su sach)) ky dang xay hoi. hieu vien cac luc va hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (su sach)) ky dang xay hoi. hieu vien cac luc va hanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (su sach)) ky dang xay hoi. hieu vien cac luc va hanh va cua tre*.