Perhaps you should try some spelling variations:
thu doanh » thu oanh, tri doanh, thu hoach
va nghiem » van nghiem, va nghiep, vao nghien
sach dao » lanh dao
dao nghe » day nghe, da nghe, dat nghe
duoc hoc » quoc hoi
te sach » toc sach
nghe d » nghe di, nghe _, nghe 新
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: (( te sach dao nghe d hoc ) or ( thu doanh ((va nghiem) OR (va nghien)) duoc hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach dao nghe d hoc ) OR ( thu doanh ((va nghiem) OR (va nghien)) duoc hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( te sach dao nghe d hoc ) or ( thu doanh ((va nghiem) OR (va nghien)) duoc hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( te sach dao nghe d hoc ) or ( thu doanh ((va nghiem) OR (va nghien)) duoc hoc ))*.