Perhaps you should try some spelling variations:
dien quang » diep quang, trien quang, lien quan
danh thanh » dinh thanh, nhanh thanh, dong thanh
dang thanh » dong thanh, dang hanh, hoang thanh
tranh cua » doanh cua, manh cua
cua trong » cua truong, cua trung, qua trong
ban thanh » ban hanh, ban hang
hoc dien » hoc hien, hoc vien, hoc dieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc dien quang - canh tranh cua trong cong ((ban thanh) or (((danh thanh) or (dang thanh)))) lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc dien quang - canh tranh cua trong cong ((ban thanh) OR (((danh thanh) OR (dang thanh)))) lap.
• Adding a wildcard symbol may retrieve word variants: hoc dien quang - canh tranh cua trong cong ((ban thanh) or (((danh thanh) or (dang thanh)))) lap*.