Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hien xanh » hien hanh, hien nhanh, hien khanh
can tranh » tan tran, van ranh, co tranh
khoa dung » hoc dung, khoa cong
dung cong » dung trong
cong van » cong vang, cong san, song van
van tai » von tai, van tuan
tai tap » bai tap, tai tao, hai tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien xanh) OR (chieu xanh)) - ((canh tranh) or (can tranh)) khoa dung cong van tai tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (chieu xanh)) - ((canh tranh) OR (can tranh)) khoa dung cong van tai tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) OR (chieu xanh)) - ((canh tranh) or (can tranh)) khoa dung cong van tai tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) OR (chieu xanh)) - ((canh tranh) or (can tranh)) khoa dung cong van tai tap*.