Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
thuc nghiem » trac nghiem
nghiem duoc » nghiem thuoc, nghe duoc
canh trinh » canh tranh, hanh trinh, canh tinh
khach thuc » thach thuc, khac phuc, cach thuc
nghien d » nghiem d, nghien o, nghiem de
vu khach » vu khanh, vu khac, vay khach
duoc hoi » quoc hoi, duoc hoc, duoc si
bo canh » kho canh
d hoc » du hoc, ad hoc, de hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( bo canh trinh nghien d hoc ) or ( vu khach thuc nghiem duoc hoi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( bo canh trinh nghien d hoc ) OR ( vu khach thuc nghiem duoc hoi )).
• Adding a wildcard symbol may retrieve word variants: (( bo canh trinh nghien d hoc ) or ( vu khach thuc nghiem duoc hoi ))*.