Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cach » vien bach, vien cac, vien canh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cach tu » cach thuc
cua tre » cua te, cuu tre, cua triet
ca dan » ca dao
vi cua » vai cua, di cua
x hoi » o hoi, x ho, 5 hoi

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 ky nang ((x hoi) or (xa hoi)). hieu vien cach tu ((ca dan) or (cac dan)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (xa hoi)). hieu vien cach tu ((ca dan) OR (cac dan)) vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((x hoi) or (xa hoi)). hieu vien cach tu ((ca dan) or (cac dan)) vi cua tre*.