Perhaps you should try some spelling variations:
nghiem quoc » nghiem nuoc, nghiep quoc, nghiem thuoc
nghiem duoc » nghiem thuoc, nghe duoc
thu nghiem » thuc nghiem, thi nghiem
khach thi » khach trai, quach thi, nhanh thi
khanh thu » nhanh thu, thanh thu, khanh thuan
khac thi » khau thi, khuc thi, khuat thi
vu khanh » vu thanh, van khanh, duy khanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( vu ((khach thi) OR (khac thi)) nghiem duoc hoc ) or ( vu khanh thu nghiem quoc hoi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( vu ((khach thi) OR (khac thi)) nghiem duoc hoc ) OR ( vu khanh thu nghiem quoc hoi )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( vu ((khach thi) OR (khac thi)) nghiem duoc hoc ) or ( vu khanh thu nghiem quoc hoi ))".
• Adding a wildcard symbol may retrieve word variants: (( vu ((khach thi) OR (khac thi)) nghiem duoc hoc ) or ( vu khanh thu nghiem quoc hoi ))*.