Perhaps you should try some spelling variations:
hanh trinh » canh tranh
chieu sang » chieu sach, chieu xanh, hieu lang
trong dan » trong dang, trong san, trong tan
hieu van » hieu va, thien van, lieu va
cua dung » cua dang, cua dong, qua dung
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.

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu sang) or (hieu van)) - ((hanh trinh) or (hanh chinh)) cua dung trong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu van)) - ((hanh trinh) OR (hanh chinh)) cua dung trong dan toan cau.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (hieu van)) - ((hanh trinh) or (hanh chinh)) cua dung trong dan toan cau*.