Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hanh tranh » canh tranh, hanh trinh, hanh trang
dong huong » dong thuong, dong duong, cong huong
hien xanh » hien hanh, hien nhanh, chieu xanh
tranh lan » tranh luan, tranh ban, thanh lan
lan dong » lang dong, luan dong, van dong
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan 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 sang)) - hanh tranh lan dong huong dan ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (chieu sang)) - hanh tranh lan dong huong dan ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (chieu sang)) - hanh tranh lan dong huong dan ((toan cau) or (toan cao))*.