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