Perhaps you should try some spelling variations:
nhung don » nhung van
hoc sach » hoc sinh, hoc cac, hoc anh
khoa toc » hoa toc, khoa thuoc, khoa quoc
khoa hoc » hoa hoc
hieu moi » nhiem moi, hieu so, hieu bo
nhung bo » nhung bi, nhung bai, trung bo
moi cua » hoi cua, doi cua, moi quan
ho vi » hoc vi, hoa vi, ho voi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((khoa toc) or (khoa hoc)) hieu moi cua ets : ((nhung bo) OR (nhung don)) ho vi đai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((khoa toc) OR (khoa hoc)) hieu moi cua ets : ((nhung bo) OR (nhung don)) ho vi đai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((khoa toc) or (khoa hoc)) hieu moi cua ets : ((nhung bo) OR (nhung don)) ho vi đai".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((khoa toc) or (khoa hoc)) hieu moi cua ets : ((nhung bo) OR (nhung don)) ho vi đai*.