Perhaps you should try some spelling variations:
thang nguoi » thanh nguoi, thong nguoi, nhung nguoi
chieu sang » chieu sach, chieu xanh, hieu lang
tang nguoi » tang nguon, nang nguoi, thanh nguoi
doi chieu » doc hieu, doi chi, ho chieu
tranh cac » trinh cac, thanh cac, tranh cai
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "doi chieu sang - canh tranh cac ((thang nguoi) OR (tang nguoi)) dan toan cau~".
• Adding a wildcard symbol may retrieve word variants: doi chieu sang - canh tranh cac ((thang nguoi) OR (tang nguoi)) dan toan cau*.