Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
cach trinh » hanh trinh, sach tranh, cac tinh
trinh cong » trinh dung
sach phan » sach han, sach phat, sach phap
mach phan » cach pha, dich phan, sach phat
cong khi » cong thai, khong khi, co khi
tu cach » tu cac

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