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