Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
thi nghiem » thuc nghiem
nghiem dan » nghiem ban, nghiem van, nghiem dau
canh trinh » canh tranh, hanh trinh, canh tinh
nghien ban » nghiem ban, nghiep ban, nghiep bang
sach thi » sach thu, sach tai, sach thieu
te sach » toc sach
tu canh » thu canh, tu chanh, tu can
ban hoc » bang hoc, van hoc, bai 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 thi nghiem dan toc ) or ( tu canh trinh nghien ban hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach thi nghiem dan toc ) OR ( tu canh trinh nghien ban hoc ))*.