Perhaps you should try some spelling variations:
thuong dong » phuong dong, tuong dong, chuong dong
thieu xanh » chieu xanh, hieu manh, thien anh
hien hanh » dieu hanh
than tinh » thanh tinh, than kinh, thai tinh
dong dan » dong danh, duong dan, dong san
dan than » dan chan, ban than, van than
than tap » toan tap, han tap, phan tap
tinh va » tich va, trinh van, trinh vat

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu xanh) or (hien hanh)) - than tinh va thuong dong dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (hien hanh)) - than tinh va thuong dong dan than tap*.