Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
chu quang » chat quang, vu quang
dung cong » dung trong
tinh cua » trinh cua, sinh cua, tranh cua
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap
hoi chu » hoi chuc

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi chu quang - thanh ((tinh cua) or (tinh chat)) dung cong thanh ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi chu quang - thanh ((tinh cua) OR (tinh chat)) dung cong thanh ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: hoi chu quang - thanh ((tinh cua) or (tinh chat)) dung cong thanh ((toan cau) or (toan cao))*.