Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
thien danh » thien anh, thien dang, thien thanh
nhung cong » dung cong, thong cong, hang cong
cong hach » cong sach, cong thanh, cong khanh
hach toan » thanh toan, manh toan
trang va » tran van
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu nganh) or (thien danh)) - hanh ((trang va) or (hang va)) nhung cong hach toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (thien danh)) - hanh ((trang va) OR (hang va)) nhung cong hach toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (thien danh)) - hanh ((trang va) or (hang va)) nhung cong hach toan cau*.