Perhaps you should try some spelling variations:
khanh trinh » hanh trinh, thanh trinh, nhanh tinh
sach trinh » sach tranh, hanh trinh, sach kinh
sach tren » sach tien, sach tranh
trinh thi » trinh tai, dinh thi, trinh tu
thi duoc » chi duoc, thi nuoc, thi quoc
duoc hoc » quoc hoi
nghe vi » nghe va, nghe noi
vi hoc » li hoc, va hoc

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) or (sach tren)) nghe vi hoc ) or ( duy khanh trinh thi duoc hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te ((sach trinh) OR (sach tren)) nghe vi hoc ) OR ( duy khanh trinh thi duoc hoc )).
• Adding a wildcard symbol may retrieve word variants: (( te ((sach trinh) or (sach tren)) nghe vi hoc ) or ( duy khanh trinh thi duoc hoc ))*.