Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien bich » phien dich, chien dich, mien dich
bich ngoc » bich nga, dinh ngoc
so sach » so sanh, bo sach, hoc sach
co sach » bo sach, cuon sach, hoc sach
ngoc ca » ngoc ha, ngoc chau, ngoc canh
ca dan » cac dan, ca dao
dan di » danh di, dan da, dan de
di cua » dai cua, doi cua, de cua
cua tu » cua tuc, cua su, cua cu
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: ((so sach) or (co sach)) ky nang ((x hoi) OR (xa hoi)). hieu hien bich ngoc ca dan di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ky nang ((x hoi) OR (xa hoi)). hieu hien bich ngoc ca dan di cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (co sach)) ky nang ((x hoi) OR (xa hoi)). hieu hien bich ngoc ca dan di cua tu*".