Perhaps you should try some spelling variations:
canh trinh » canh tranh, canh tinh, anh trinh
hanh trinh » canh tranh, hanh chinh
tieu sach » chieu sach, dien sach, te sach
khoa dung » hoc dung, khoa cong
dung cong » dung trong
cong vang » cong lang, cong quang, cong ngang
vang tan » van tan, tang tan, vang tao
tan ban » toan ban, tang ban, van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo tieu sach - ((canh trinh) or (hanh trinh)) khoa dung cong vang tan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - ((canh trinh) OR (hanh trinh)) khoa dung cong vang tan ban*.