Perhaps you should try some spelling variations:
nguyen tai » nguyen thai, nguyen thi, nguyen tac
xuyen tai » xuyen tac, truyen tai, luyen thi
cong cong » cong dong, trong cong, dang cong
dung cong » dung trong
cac chu » cac thu, cac che, cac khu
co bang » cao bang, con bang, co ban
bang ly » hang ly
ky thu » ly thu, ky thi, ky thuat
ly ky » ly y

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((nguyen tai) or (xuyen tai)) cac chu đe co bang ly ky thu ((cong cong) OR (dung cong))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((nguyen tai) OR (xuyen tai)) cac chu đe co bang ly ky thu ((cong cong) OR (dung cong))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((nguyen tai) or (xuyen tai)) cac chu đe co bang ly ky thu ((cong cong) OR (dung cong))*".