Perhaps you should try some spelling variations:
hieu thien » hieu hien, chieu chien, dieu khien
thien hach » thien thanh, hien hanh
thanh van » thanh san, thanh toan, thanh phan
toc sach » hoc sach, doc sach, thuoc sach
hach duc » thach duc, hanh duoc, sach duoc
duc gia » quoc gia
van cac » van hac, van cau, van bac
cac tre » cac tro, cac tru, cac trieu
x hoi » xa hoi, o hoi, 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: ((te sach) or (toc sach)) ky nang ((x hoi) or (x ho)). hieu thien hach duc gia thanh van cac tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang ((x hoi) OR (x ho)). hieu thien hach duc gia thanh van cac tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang ((x hoi) or (x ho)). hieu thien hach duc gia thanh van cac tre*.