Perhaps you should try some spelling variations:
dang tan » dang tran, dang toan, dang van
van chat » cao chat
thiet he » thiet ke, thiet de, thien hue
thien he » thien hue, thien ke, trien he
quan den » quan doan, quan he, quan doi
ky dang » ky nang, ky danh
tan van » tran van, tang van, luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: cong trinh ky dang tan van chat luong ((thiet he) OR (thien he)) quan den~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "cong trinh ky dang tan van chat luong ((thiet he) OR (thien he)) quan den*".