Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
nhan thai » nhanh thai, nhan tai, nhan tham
vien cac » vien bach, vien dai, vien da
thu sach » thuat sach, thuoc sach, thu hoach
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
cua tre » cuu tre, cua triet, dua tren
va nhan » van nhan, ca nhan, va phan
tu sach » su sach, te sach, tu cach
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
cua te » cua tu

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) or (thu sach)) ky tang xa hoi. hieu vien cac nuoc va nhan thai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky tang xa hoi. hieu vien cac nuoc va nhan thai ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky tang xa hoi. hieu vien cac nuoc va nhan thai ((cua tre) OR (cua te))*".