Perhaps you should try some spelling variations:
hien xanh » hien nhanh, chieu xanh, hien khanh
hien hanh » dieu hanh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
cong hach » cong sach, cong thanh, cong khanh
hach toan » thanh toan, manh toan
qua dung » quang dung, qua song, qua cong
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 xanh) or (hien hanh)) - hanh tinh ((qua dung) OR (su dung)) cong hach toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (hien hanh)) - hanh tinh ((qua dung) OR (su dung)) cong hach toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) or (hien hanh)) - hanh tinh ((qua dung) OR (su dung)) cong hach toan tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (hien hanh)) - hanh tinh ((qua dung) OR (su dung)) cong hach toan tap*.