Perhaps you should try some spelling variations:
hien xanh » hien hanh, hien nhanh, chieu xanh
hanh tran » hanh trang, thanh tran, hanh tram
hang cong » dang cong, hang nong, bang cong
tran van » luan van
van hang » van khang, van hoang, van thang
san chan » san chang, dan chan, ban chan
san chay » san pham, van chat, dan chan

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 tran van hang cong ((san chan) or (san chay)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh tran van hang cong ((san chan) OR (san chay)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh tran van hang cong ((san chan) or (san chay)) cau*.