Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
cham duc » pham duc, cham soc, pham duy
thu nang » thi nang, thu hang, thu bang
dua tren » dung tren
sach thu » sach thue, sach thieu, sach tham
te sach » toc sach
duc gia » quoc gia
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
dai tai » dai thao
dai hai » dai han, dai hoi, dai thao
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach thu nang ((dai hai) OR (dai tai)). hieu vu cham duc gia thanh hai ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach thu nang ((dai hai) OR (dai tai)). hieu vu cham duc gia thanh hai ((dua tren) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach thu nang ((dai hai) OR (dai tai)). hieu vu cham duc gia thanh hai ((dua tren) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: te sach thu nang ((dai hai) OR (dai tai)). hieu vu cham duc gia thanh hai ((dua tren) or (cuu tre))*.