Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hoc thieu » toc thieu, hoc hien
chua dang » cua dang, chua dong, chua nang
dang cong » dung cong
anh dang » anh dong, anh dung, anh bang
manh van » anh van, menh van, hanh van
canh van » anh van, can van, cach van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sach - ((canh tranh) or (anh dang)) chua dang cong ((manh van) OR (canh van)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - ((canh tranh) OR (anh dang)) chua dang cong ((manh van) OR (canh van)) ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sach - ((canh tranh) or (anh dang)) chua dang cong ((manh van) OR (canh van)) ban".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - ((canh tranh) or (anh dang)) chua dang cong ((manh van) OR (canh van)) ban*.