Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
hien xanh » hien nhanh, chieu xanh, hien khanh
hien hanh » dieu hanh
tranh cua » doanh cua, manh cua
tong song » tong cong, song song, dong song
cua tong » cua cong, cua dong, cua nong
song cao » cong cao, dong cao, song ca
chat cau » chat cao, chat va, chat ban
chat cam » chat cao, thuat cam, chat va

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) OR (hien hanh)) - hanh tranh cua tong song cao ((chat cau) OR (chat cam))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) or (hien hanh)) - hanh tranh cua tong song cao ((chat cau) OR (chat cam))~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (hien hanh)) - hanh tranh cua tong song cao ((chat cau) OR (chat cam))*.