Perhaps you should try some spelling variations:
thanh trung » thanh tung
theo chieu » theo tieu, theo chu, thi chieu
tong cong » trong cong, cong cong, dung cong
anh quang » anh xquang, anh quan, tinh quang
ho chieu » hoc thieu, doi chieu, mot chieu
trung ha » trung hoc, trung tam, trung cap
ha tong » han tong, ha dong, ha tang

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 ha tong cong ((anh quang) OR (nhanh quang)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (ho chieu)) xanh - thanh trung ha tong cong ((anh quang) OR (nhanh quang)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((theo chieu) or (ho chieu)) xanh - thanh trung ha tong cong ((anh quang) OR (nhanh quang)) cao".
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) or (ho chieu)) xanh - thanh trung ha tong cong ((anh quang) OR (nhanh quang)) cao*.