Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trang, lanh tranh
hanh trinh » canh tranh, hanh chinh
hien xanh » hien hanh, hien nhanh, chieu xanh
cua tong » cua cong, cua nong, cua song
cua dong » chua dong, cua cong, cua dang
cong tac » cong ty
tac khan » tac nhan, cac khoan, tac chuan
khan ap » khan cap, han ap, khan dam

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 hien xanh - ((hanh tranh) OR (hanh trinh)) ((cua tong) OR (cua dong)) cong tac khan ap~.
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - ((hanh tranh) or (hanh trinh)) ((cua tong) or (cua dong)) cong tac khan ap*.