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
dinh tri » chinh tri
danh vi » hanh vi, dinh vi, danh di
ngoc va » nuoc va, ngoc ha, goc va
co sach » bo sach, cuon sach, hoc sach
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
ha hoi » hoa hoi, ha noi, xa hoi
cua su » qua su

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ((ky lang) OR (ky tang)) ha hoi. hieu hien bich ngoc va ((danh vi) or (dinh tri)) cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ((ky lang) OR (ky tang)) ha hoi. hieu hien bich ngoc va ((danh vi) OR (dinh tri)) cua su*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ((ky lang) OR (ky tang)) ha hoi. hieu hien bich ngoc va ((danh vi) or (dinh tri)) cua su*".