Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thuat lanh » thuat lap, thuat san
cach khong » cach phong, cac phong, bach khang
truc thuc » truc thuoc, thuc thuc, truc thuy
thuc cach » truoc cach, thuc hanh, tuc cac
khong khi » khong he
khi thong » khi phong, khi tuong, thi thuong

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuoc sach) or (thuat lanh)) truc thuc cach khong khi thong~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (thuat lanh)) truc thuc cach khong khi thong.
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) or (thuat lanh)) truc thuc cach khong khi thong*.