Perhaps you should try some spelling variations:
tranh nghiem » trac nghiem, trinh nghien, trai nghiem
trach nhiem » trac nghiem
cong trach » thong trach, cong tac, cong trinh
thuoc sach » hoc sach, nuoc sach, thuat sach
sach tranh » canh tranh
duoc hoc » quoc hoi
nghiem y » nghiep y, nghiem _, nghiem d
du hoc » tu hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( thu cong trach nhiem ((du hoc) OR (duoc hoc)) ) or ( thuoc sach tranh nghiem y hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thu cong trach nhiem ((du hoc) OR (duoc hoc)) ) OR ( thuoc sach tranh nghiem y hoc ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( thu cong trach nhiem ((du hoc) OR (duoc hoc)) ) or ( thuoc sach tranh nghiem y hoc ))*".