Perhaps you should try some spelling variations:
hien sach » dien sach, kien sach, thien hach
thang cua » thong cua, hang cua, tang cua
hang cong » dang cong, hang nong, bang cong
dan thanh » dang thanh, danh thanh, ban thanh
thanh cac » hanh cac, thanh bac, thanh ca
than cua » nhan cua, thai cua, ban cua
cong dan » cong san, cong tan, huong dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien sach - cang ((thang cua) OR (than cua)) hang cong dan thanh cac~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien sach - cang ((thang cua) OR (than cua)) hang cong dan thanh cac".
• Adding a wildcard symbol may retrieve word variants: hoc hien sach - cang ((thang cua) OR (than cua)) hang cong dan thanh cac*.