Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
nghiem duoc » nghiem thuoc
canh trinh » canh tranh, hanh trinh, canh tinh
sach trac » sach truc, sach tranh, sach tham
nghe duoc » nghe nuoi, che duoc
nghien de » nghiem de, nghiep ke, nghiem d
thu canh » thuc hanh, thu cong, thu ban
te sach » toc sach
de hoc » te hoc, du hoc, dien hoc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach trac ((nghiem duoc) OR (nghe duoc)) hoc ) OR ( thu canh trinh nghien de hoc ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( te sach trac ((nghiem duoc) OR (nghe duoc)) hoc ) or ( thu canh trinh nghien de hoc ))~".
• Adding a wildcard symbol may retrieve word variants: (( te sach trac ((nghiem duoc) OR (nghe duoc)) hoc ) or ( thu canh trinh nghien de hoc ))*.