Perhaps you should try some spelling variations:
tham nghiem » trac nghiem, thuc nghiem, thi nghiem
trach nhiem » trac nghiem
thuoc sach » hoc sach, nuoc sach, thuoc sinh
thuat sach » thuat san
thuat lanh » thuat lap, thuat san
sach tham » sach nha
nghiem su » nghiem xu, nghiem ngu, nghiem dau
nhiem d » nghiem d, nghiem de, nghiem do
su hoc » tu hoc, du hoc, so hoc
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: (( thuoc sach tham nghiem su hoc ) or ( ((thuat sach) OR (thuat lanh)) trach nhiem d hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thuoc sach tham nghiem su hoc ) OR ( ((thuat sach) OR (thuat lanh)) trach nhiem d hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( thuoc sach tham nghiem su hoc ) or ( ((thuat sach) OR (thuat lanh)) trach nhiem d hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( thuoc sach tham nghiem su hoc ) or ( ((thuat sach) OR (thuat lanh)) trach nhiem d hoc ))*.