Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
tranh cua » doanh cua, manh cua
cong cong » cong dong, trong cong, dung cong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
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: theo ((hieu lang) OR (chieu sang)) - hanh tranh cua cong cong tap toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu lang) OR (chieu sang)) - hanh tranh cua cong cong tap toan cao".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) OR (chieu sang)) - hanh tranh cua cong cong tap toan cao*.