Perhaps you should try some spelling variations:
dang khoi » dung khoa, hang khoa
tham cong » pham cong, thai cong, tham cung
sach pha » sach phat, sach phap, sach nha
pha dang » phan dang, pham dang, ha dang
cong khi » cong thai, khong khi, co khi
bo sach » co sach, hoc sach
su sach » vu sach
so sach » so sanh, co sach, hoc sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( bo sach pha dang khoi đong luc ) or ( ((su sach) OR (so sach)) tham cong khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( bo sach pha dang khoi đong luc ) OR ( ((su sach) OR (so sach)) tham cong khi đong luc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( bo sach pha dang khoi đong luc ) or ( ((su sach) OR (so sach)) tham cong khi đong luc ))".
• Adding a wildcard symbol may retrieve word variants: (( bo sach pha dang khoi đong luc ) or ( ((su sach) OR (so sach)) tham cong khi đong luc ))*.