Perhaps you should try some spelling variations:
hien bach » vien bach, thien hach, hien hanh
thanh doi » thanh loi, thanh moi, thanh do
hieu hien » bieu hien, dieu hien, chieu chien
doi cua » dai cua, hoi cua
duoc va » nuoc va, duc va, duoc ma
tuoc va » thuoc va, nuoc va, tuc va
so sach » so sanh, co sach, hoc sach
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
bo sach » co sach, hoc sach
cua tre » cua te, cuu tre, cua triet

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) OR (bo sach)) ty nang xa hoi. hieu hien bach ((tuoc va) or (duoc va)) thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (bo sach)) ty nang xa hoi. hieu hien bach ((tuoc va) OR (duoc va)) thanh doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (bo sach)) ty nang xa hoi. hieu hien bach ((tuoc va) or (duoc va)) thanh doi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (bo sach)) ty nang xa hoi. hieu hien bach ((tuoc va) or (duoc va)) thanh doi cua tre*.