Perhaps you should try some spelling variations:
thu nghiem » thuc nghiem, thi nghiem
hoach thu » hoach thay, doanh thu, hoach su
sach dao » lanh dao
dao nghe » day nghe, da nghe, dat nghe
tu sach » thu sach, su sach, te sach
su hoc » so hoc, su ho, su hoa
du hoc » duoc hoc
tu hoc » te 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 dao nghe _ hoc ) or ( thu hoach thu nghiem ((((su hoc) or (du hoc))) or (tu hoc)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach dao nghe _ hoc ) OR ( thu hoach thu nghiem ((((su hoc) OR (du hoc))) OR (tu hoc)) )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach dao nghe _ hoc ) or ( thu hoach thu nghiem ((((su hoc) or (du hoc))) or (tu hoc)) ))*.