Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
bach luoc » bach tuoc, sach duoc, sach nuoc
nang doc » nang luc
luoc van » luoc can, luoc va, luc van
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
nang co » nang cao, nang noi, nang hoc
tai cuu » tai cuc, tai buu, tai cua
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky ((nang co) or (nang doc)) hoi. hieu vien bach luoc van hanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky ((nang co) OR (nang doc)) hoi. hieu vien bach luoc van hanh tai cuu tre.
• Adding a wildcard symbol may retrieve word variants: so sach ky ((nang co) or (nang doc)) hoi. hieu vien bach luoc van hanh tai cuu tre*.