Perhaps you should try some spelling variations:
xay nghiem » xet nghiem, day nghiep, van nghiem
nghe 新 » nghe _
thu sach » thuat sach, thuoc sach, khau sach
tu sach » su sach, te sach, tu cach
da nghe » day nghe, va nghe, dang nghe
新 hoc » y hoc, _ hoc, o hoc
su hoc » tu hoc, du hoc, so hoc
mo hoc » mon hoc, co 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 sach) OR (thu sach)) da nghe 新 hoc ) or ( thu hoach xay nghiem ((su hoc) or (mo hoc)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((tu sach) OR (thu sach)) da nghe 新 hoc ) OR ( thu hoach xay nghiem ((su hoc) OR (mo hoc)) )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((tu sach) OR (thu sach)) da nghe 新 hoc ) or ( thu hoach xay nghiem ((su hoc) or (mo hoc)) ))".
• Adding a wildcard symbol may retrieve word variants: (( ((tu sach) OR (thu sach)) da nghe 新 hoc ) or ( thu hoach xay nghiem ((su hoc) or (mo hoc)) ))*.