Perhaps you should try some spelling variations:
sach hanh » sach danh, sach han, sac hanh
hanh cong » thanh cong, hang cong, hanh dong
sach ngan » sach ngon, sach nha, sach han
cong khi » cong thai, khong khi, co khi
so sach » so sanh, bo sach, co sach
ngan y » nganh y, nhan y, nganh ky
y khi » ly khi, ky khi, my khi

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 hanh cong khi đong luc ) or ( so sach ngan y khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sach hanh cong khi đong luc ) OR ( so sach ngan y khi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( so sach hanh cong khi đong luc ) or ( so sach ngan y khi đong luc ))*.