Perhaps you should try some spelling variations:
thieu chi » thieu nhi, hieu chi, tieu chi
nhung don » nhung van
khoa toc » khoa hoc, khoa thuoc, khoa quoc
nhung bo » nhung bi, nhung bai, trung bo
tu sach » thu sach, su sach, te sach
hoa toc » hoa hoc, ho toc, hoa doc
chi cua » chi cuc, khi cua, cuoi cua
oc vi » hoc vi, doc vi

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 ((khoa toc) OR (hoa toc)) thieu chi cua ets : ((nhung bo) or (nhung don)) oc vi đai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((khoa toc) OR (hoa toc)) thieu chi cua ets : ((nhung bo) OR (nhung don)) oc vi đai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((khoa toc) OR (hoa toc)) thieu chi cua ets : ((nhung bo) or (nhung don)) oc vi đai".
• Adding a wildcard symbol may retrieve word variants: tu sach ((khoa toc) OR (hoa toc)) thieu chi cua ets : ((nhung bo) or (nhung don)) oc vi đai*.