Perhaps you should try some spelling variations:
thanh thong » thanh thuong, thanh hong, thanh thang
thong huong » thong thuong, thong duong, thong thong
thieu xanh » chieu xanh, thien anh, thien danh
hieu manh » chieu xanh, hieu nganh, dieu hanh
thong va » thong cua, truong va, thong qua
va thong » va thuong, va phuong, he thong
ban toan » bai toan, ban than, van toan

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 (hieu manh)) - thanh thong va thong huong ((ban toan) or (bai tap)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (hieu manh)) - thanh thong va thong huong ((ban toan) OR (bai tap)) cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (hieu manh)) - thanh thong va thong huong ((ban toan) or (bai tap)) cao*.