Perhaps you should try some spelling variations:
sach trien » sach tien, sach tren, sach thieu
trien cong » thien cong
tran dong » tran hong, tran dang, tran cong
tran dung » tran dang, tran hung, tran quang
thu sach » tu sach, thuat sach, thuoc sach
cong khi » cong thai, khong khi, co khi
su sach » so sach, vu 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 ((tran dong) OR (tran dung)) khi đong luc ) or ( thu sach trien cong khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach ((tran dong) OR (tran dung)) khi đong luc ) OR ( thu sach trien cong khi đong luc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( su sach ((tran dong) OR (tran dung)) khi đong luc ) or ( thu sach trien cong khi đong luc ))".
• Adding a wildcard symbol may retrieve word variants: (( su sach ((tran dong) OR (tran dung)) khi đong luc ) or ( thu sach trien cong khi đong luc ))*.