Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh quan » tinh quang, trinh luat, trinh han
hoc thieu » toc thieu, hoc hien
hang nong » thang long
doc hieu » toc thieu, hoc hien
tac toan » tap toan, tam toan, hach toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doc hieu) or (hoc thieu)) xanh - hanh trinh quan ((hang nong) OR (han tong)) tac toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc thieu)) xanh - hanh trinh quan ((hang nong) OR (han tong)) tac toan ban*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) or (hoc thieu)) xanh - hanh trinh quan ((hang nong) OR (han tong)) tac toan ban*".