Perhaps you should try some spelling variations:
sach tranh » canh tranh
tranh cong » thanh cong, trinh cong, tran cong
sach nganh » sach ngan, cac nganh, sach danh
cong thanh » dong thanh, cong tan, truong thanh
cong khi » cong thai, khong khi, co khi
su sach » so sach, vu sach
te sach » toc sach

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

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