Perhaps you should try some spelling variations:
hanh trinh » canh tranh
hien xanh » hien hanh, hien nhanh, chieu xanh
bang cong » dang cong, bang song, hang cong
cong van » cong vang, cong san, song van
va bang » va nang, va lang, va ban
tan cau » toan cau, tan ca, tao cau
van cau » van dau, van hau, van chat

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 - ((hanh trinh) or (hanh chinh)) va bang cong van ((tan cau) OR (van cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - ((hanh trinh) OR (hanh chinh)) va bang cong van ((tan cau) OR (van cau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - ((hanh trinh) or (hanh chinh)) va bang cong van ((tan cau) OR (van cau))".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - ((hanh trinh) or (hanh chinh)) va bang cong van ((tan cau) OR (van cau))*.