Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
hanh tranh » canh tranh, hanh trinh, hanh trang
hoc thien » hoc hien, hoc thieu, hoc thiet
tranh cua » doanh cua, manh cua
hang cong » dang cong, hang nong, bang cong
van khoan » van khoa, van hoan, toan khoan
khoan cam » khoa cam, khoan va, phan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien hach - hanh tranh cua ((trong cong) or (hang cong)) van khoan cam~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh tranh cua ((trong cong) OR (hang cong)) van khoan cam.
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh tranh cua ((trong cong) or (hang cong)) van khoan cam*.