Perhaps you should try some spelling variations:
trinh nghien » kinh nghiem, trinh thiet, trinh dien
khanh trinh » hanh trinh, thanh trinh, nhanh tinh
trinh phap » trinh phan, trinh han, trinh chat
trinh nghe » trinh he, trinh nha
so sach » so sanh, bo sach, co sach
nghe du » nghe duc, nghe xu, nghe di
tu hoc » te hoc
du hoc » duoc hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sach ((trinh nghien) or (trinh phap)) tu hoc ) or ( duy khanh trinh nghe du hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sach ((trinh nghien) OR (trinh phap)) tu hoc ) OR ( duy khanh trinh nghe du hoc )).
• Adding a wildcard symbol may retrieve word variants: (( so sach ((trinh nghien) or (trinh phap)) tu hoc ) or ( duy khanh trinh nghe du hoc ))*.