Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
hang cong » dang cong, hang nong, bang cong
bang song » nang song
hoc hieu » hoc thieu, hoc hien, doc hieu
trinh va » trinh van, trinh vat, trinh ve
dan than » dan chan, ban than, van than
than cap » khan cap, thanh lap, thanh cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - hanh trinh va ((((hang cong) or (thanh cong))) or (bang song)) dan than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - hanh trinh va ((((hang cong) OR (thanh cong))) OR (bang song)) dan than cap.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - hanh trinh va ((((hang cong) or (thanh cong))) or (bang song)) dan than cap*.