Perhaps you should try some spelling variations:
thai nghien » thai nguyen, thi nghiem, phap nghien
khach thai » khach trai, khac trai, nhanh thai
nghiem va » nghiep vua, nghiep vu
nghiep va » nghiep vu
tan khach » can khach, tran khanh, van khanh
nghien vu » nghiep vu, nghien cuu, nghiep vua
khac thi » khau thi, khuc thi, khuat thi
tu khac » vu khac, su khac, ta khac
vu hoc » tu hoc, va hoc, du hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu khac thi ((nghiem va) or (nghiep va)) hoc ) or ( tan khach thai nghien vu hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu khac thi ((nghiem va) OR (nghiep va)) hoc ) OR ( tan khach thai nghien vu hoc )).
• Adding a wildcard symbol may retrieve word variants: (( tu khac thi ((nghiem va) or (nghiep va)) hoc ) or ( tan khach thai nghien vu hoc ))*.