Perhaps you should try some spelling variations:
sach trinh » sach tranh, hanh trinh, sach kinh
trinh cong » trinh dung
sach ngan » sach ngon, sach nha, sach han
cong khi » cong thai, khong khi, cong ha
su sach » vu sach
ngan co » nganh co, ngon co, nhan co
so sach » so sanh, bo sach, co sach

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

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