Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
hanh trung » thanh trung, hanh trang, manh trung
hien sach » dien sach, thien hach, chieu sach
kien sach » dien sach, vien bach, kien mac
trung cua » truong cua, trung tuan, trung cap
dang cong » dung cong
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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) OR (kien sach)) - hanh trung cua ((thong cong) or (dang cong)) dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sach) OR (kien sach)) - hanh trung cua ((thong cong) OR (dang cong)) dan than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien sach) OR (kien sach)) - hanh trung cua ((thong cong) or (dang cong)) dan than cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) OR (kien sach)) - hanh trung cua ((thong cong) or (dang cong)) dan than cao*.