Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
chieu sang » chieu sach, chieu xanh, hieu lang
hanh nhan » thanh nhan, danh nhan, anh nhan
tong cong » trong cong, cong cong, dung cong
cong dan » cong san, cong tan, huong dan
dan nhan » danh nhan, dan chan, van nhan
nhan tai » hang tai, van tai, toan tai
nhan va » nhan dan, nhan tao, phan van
va tong » va thong, va tuong, va trong

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sang) or (thieu quang)) - hanh nhan va tong cong dan nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (thieu quang)) - hanh nhan va tong cong dan nhan tai.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (thieu quang)) - hanh nhan va tong cong dan nhan tai*.