Perhaps you should try some spelling variations:
hanh trung » thanh trung, hanh trang, manh trung
thong tinh » thuong tinh, thong minh, trong tinh
hieu lang » chieu sang, hieu quang, nhieu tang
cua thong » cua thuong, cua khong, suat thong
cua tong » cua cong, cua dong, cua nong
toan cao » toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - hanh trung ((cua thong) or (cua tong)) ((thong tinh) OR (thong tin)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - hanh trung ((cua thong) OR (cua tong)) ((thong tinh) OR (thong tin)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh trung ((cua thong) or (cua tong)) ((thong tinh) OR (thong tin)) toan cao".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh trung ((cua thong) or (cua tong)) ((thong tinh) OR (thong tin)) toan cao*.