Perhaps you should try some spelling variations:
thieu khi » thieu nhi, tien khi, hieu chi
doc bach » doc sach, dong bach, doc benh
doc hanh » hoc hanh, duc hanh, doi hanh
khoa toc » khoa hoc, hoa toc, khoa thuoc
nhung bo » nhung bi, nhung bai, nhung don
khi cua » chi cua, thai cua
so vi » so voi, so va, so li
so di » so dia, so du, so dk

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

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