Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
thang cong » thanh cong, thang long, thong cong
hoc thieu » toc thieu, hoc hien
trang van » tran van, trang va, tang van
trong van » trong cac
cong dan » cong san, cong tan, huong dan
dan van » dang van, doan van, dao 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 - hanh ((trang van) or (trong van)) thang cong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - hanh ((trang van) OR (trong van)) thang cong dan van ban*.