Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
canh trinh » canh tranh, canh tinh, anh trinh
hanh trinh » canh tranh, hanh chinh
thong cong » trong cong, thong thong, phong chong
hoc thieu » toc thieu, hoc hien
tong cong » trong cong, cong cong, dung cong
dan phan » doan phan, dan chan, van phan

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - ((canh trinh) OR (hanh trinh)) van ((thong cong) OR (tong cong)) dan phan tu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - ((canh trinh) OR (hanh trinh)) van ((thong cong) or (tong cong)) dan phan tu~".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - ((canh trinh) OR (hanh trinh)) van ((thong cong) or (tong cong)) dan phan tu*.