Perhaps you should try some spelling variations:
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hien sach » dien sach, thien hach, chieu sach
kien sach » dien sach, vien bach, kien mac
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
manh toan » thanh toan, anh tuan, tinh toan
toan tap » toan ban

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