Perhaps you should try some spelling variations:
thuong dong » phuong dong, chuong dong, huong dong
tuong dong » tuong duong, trong dong, cuong duong
hieu manh » chieu xanh, hieu nganh, dieu hanh
thien anh » thien danh, tien anh, thien thanh
than tinh » thanh tinh, than kinh, thai tinh
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 ((hieu manh) or (thien anh)) - than tinh va ((thuong dong) OR (tuong dong)) dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (thien anh)) - than tinh va ((thuong dong) OR (tuong dong)) dan than tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) or (thien anh)) - than tinh va ((thuong dong) OR (tuong dong)) dan than tap*".