Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien danh
nhung cong » dung cong, thong cong, hang cong
cong ngang » cong nhan, cong quang, cong lang
ngang toan » nganh toan, dang toan, quang toan
thien anh » thien danh, tien anh, thien thanh
toan ban » van ban
toan va » doan va, tran van, toan cao

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 (thien anh)) - thanh ((toan va) OR (toan tap)) nhung cong ngang toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (thien anh)) - thanh ((toan va) OR (toan tap)) nhung cong ngang toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) or (thien anh)) - thanh ((toan va) OR (toan tap)) nhung cong ngang toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (thien anh)) - thanh ((toan va) OR (toan tap)) nhung cong ngang toan ban*.