Perhaps you should try some spelling variations:
xay nghiem » xet nghiem, day nghiep, van nghiem
sach dao » lanh dao
dao nghe » day nghe, da nghe, dat nghe
te sach » toc sach
du hoc » tu hoc, duoc hoc
su hoc » tu hoc, su ho, su hoa
so hoc » co hoc, mo hoc, so hoa
d hoc » ad hoc, de hoc, y 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 sach dao nghe ((d hoc) or (du hoc)) ) or ( thu hoach xay nghiem ((su hoc) or (so hoc)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach dao nghe ((d hoc) OR (du hoc)) ) OR ( thu hoach xay nghiem ((su hoc) OR (so hoc)) )).
• Adding a wildcard symbol may retrieve word variants: (( te sach dao nghe ((d hoc) or (du hoc)) ) or ( thu hoach xay nghiem ((su hoc) or (so hoc)) ))*.