Perhaps you should try some spelling variations:
nghiem su » nghiem xu, nghiem ngu, nghiem dau
sach dao » lanh dao
dao nghe » day nghe, da nghe, dat nghe
hoach va » hoach xay, doanh va, hoa va
tu sach » thu sach, su sach, te sach
nghe sy » nghe so, nghe si, nghe san
hanh va » hang va, hanh vi
sy hoc » y hoc, ly hoc, so hoc
su hoc » tu hoc, du hoc, so 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 sy hoc ) or ( thu ((hoach va) or (hanh va)) nghiem su hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach dao nghe sy hoc ) OR ( thu ((hoach va) OR (hanh va)) nghiem su hoc )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach dao nghe sy hoc ) or ( thu ((hoach va) or (hanh va)) nghiem su hoc ))*.