Perhaps you should try some spelling variations:
thanh trung » thanh tung
phuong danh » phuong anh, phuong dinh, phuong hanh
theo chieu » theo tieu, theo chu, thi chieu
phuong dan » phuong doan, huong dan, phuong lan
trung qua » trung quan, trong qua, trung cua
toan thuc » toan hoc, dan thuc, nhan thuc
ho chieu » hoc thieu, doi chieu, mot chieu
qua dung » quang dung, su dung, qua song

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((theo chieu) or (ho chieu)) xanh - thanh trung qua dung ((phuong dan) OR (phuong danh)) toan thuc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (ho chieu)) xanh - thanh trung qua dung ((phuong dan) OR (phuong danh)) toan thuc.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((theo chieu) or (ho chieu)) xanh - thanh trung qua dung ((phuong dan) OR (phuong danh)) toan thuc".
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) or (ho chieu)) xanh - thanh trung qua dung ((phuong dan) OR (phuong danh)) toan thuc*.