Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
cong cong » cong dong, trong cong, dung cong
nang cham » trang cham, nang cao, nang phat
tran nhat » toan nha, tran chau
doc hieu » toc thieu, hoc thieu, hoc hien
tinh hoc » sinh hoc, tin hoc, hinh hoc
hoc cong » hoc co, cac cong, hoc dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu lang - hanh tinh hoc cong cong ((nang cham) or (tran nhat)) ran~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu lang - hanh tinh hoc cong cong ((nang cham) OR (tran nhat)) ran*.