Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thieu khi » thieu nhi, tien khi, khien khi
toc sach » hoc sach, doc sach, nuoc sach
khoa toc » khoa hoc, hoa toc, khoa thuoc
hieu chi » hieu cac, hieu moi
nhung bi » nhung bai, nhung gi
cho vi » chon vi, cho vit, cho va

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

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