Perhaps you should try some spelling variations:
cong thanh » cong trinh, cong tan, truong thanh
dong thanh » truong thanh
sach tranh » canh tranh
tranh cong » thanh cong, trinh cong, tran cong
sach phan » sach han, mach phan, sach phat
cong khi » cong thai, khong khi, co khi
te sach » toc sach
tu sach » thu sach, su sach, tu cach

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

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