Perhaps you should try some spelling variations:
hoach hoi » hoc hoi, sach hoi
nghiem su » nghiem xu, nghiem ngu, nghiem dau
hoach ha » hoach va, hoach xay, hoach su
cac cam » cad cam, cac cap, cac cay
cac cau » cac mau, bac cau, ca cau
nghe d » nghe di, nghe _, nghe 新
su hoc » tu hoc, du hoc, so hoc
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 ((cac cam) OR (cac cau)) nghe d hoc ) or ( thu ((hoach ha) or (hoach hoi)) nghiem su hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu ((cac cam) OR (cac cau)) nghe d hoc ) OR ( thu ((hoach ha) OR (hoach hoi)) nghiem su hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu ((cac cam) OR (cac cau)) nghe d hoc ) or ( thu ((hoach ha) or (hoach hoi)) nghiem su hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( tu ((cac cam) OR (cac cau)) nghe d hoc ) or ( thu ((hoach ha) or (hoach hoi)) nghiem su hoc ))*.