Perhaps you should try some spelling variations:
sach trinh » sach tranh, hanh trinh, sach kinh
sach tran » sach tranh, sach tren, vach tran
tran cong » tran hong, trien cong, tran hoang
cong thai » cong hai, hong thai, cong thanh
trinh co » trinh do, trinh cong, trinh hoa
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 trinh co khi đong luc ) or ( tu sach tran cong thai đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach trinh co khi đong luc ) OR ( tu sach tran cong thai đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach trinh co khi đong luc ) or ( tu sach tran cong thai đong luc ))*.