Perhaps you should try some spelling variations:
hanh cong » thanh cong, hang cong, hanh dong
sach tham » sach nha
tham cong » pham cong, thai cong, tham cung
sac hanh » sach danh, bac thanh, cac thanh
cong khi » cong thai, khong khi, co khi
te sach » toc sach
so sac » so sach, so dac

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sac hanh cong khi đong luc ) or ( te sach tham cong khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sac hanh cong khi đong luc ) OR ( te sach tham cong khi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( so sac hanh cong khi đong luc ) or ( te sach tham cong khi đong luc ))*.