Perhaps you should try some spelling variations:
trach nhiem » trac nghiem
phat trach » phat thanh, phan tach, phan trac
sach trinh » sach tranh, hanh trinh, sach kinh
nghien du » nghiep du, nghiem dau, nghiep dau
nhiem tu » nhiem thuc, nhiem huu, nghiem su
te phat » tu phat
te sach » toc sach
tu hoc » te 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 phat trach nhiem tu hoc ) or ( te sach trinh ((nghien du) OR (nghien cuu)) hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te phat trach nhiem tu hoc ) OR ( te sach trinh ((nghien du) OR (nghien cuu)) hoc ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( te phat trach nhiem tu hoc ) or ( te sach trinh ((nghien du) OR (nghien cuu)) hoc ))*".