Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
nghiem quoc » nghiem duoc, nghiem nuoc, nghiep quoc
thi nghiem » thuc nghiem
khach thi » khac thi, khach trai, quach thi
kho canh » kho tang, thu canh, cho can
nghien d » nghiem d, nghien o, nghiem de
vu khach » vu khanh, vu khac, vay khach
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) OR (kho canh)) trinh nghien d hoc ) or ( vu khach thi nghiem quoc hoi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((bo canh) OR (kho canh)) trinh nghien d hoc ) OR ( vu khach thi nghiem quoc hoi )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((bo canh) OR (kho canh)) trinh nghien d hoc ) or ( vu khach thi nghiem quoc hoi ))".
• Adding a wildcard symbol may retrieve word variants: (( ((bo canh) OR (kho canh)) trinh nghien d hoc ) or ( vu khach thi nghiem quoc hoi ))*.