Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
trinh dieu » trinh dien, tinh dieu, trinh dinh
tien duan » tien dua, tien huan, tien quang
hoc tien » hoc tieng, hoc hien, hoc vien
van cua » vang cua, ban cua, dan cua
viet n1 » viet nm, viet nam, viet anh
viet 1 » viet o, viet 2, viet 4

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

• Performing a fuzzy search may retrieve terms with similar spellings: giao ((trinh thiet) or (trinh dieu)) luan van cua nguoi ((viet n1) OR (viet 1)) hoc tien duan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: giao ((trinh thiet) OR (trinh dieu)) luan van cua nguoi ((viet n1) OR (viet 1)) hoc tien duan.
• The words AND, OR and NOT may confuse the search; try adding quotes: "giao ((trinh thiet) or (trinh dieu)) luan van cua nguoi ((viet n1) OR (viet 1)) hoc tien duan".
• Adding a wildcard symbol may retrieve word variants: giao ((trinh thiet) or (trinh dieu)) luan van cua nguoi ((viet n1) OR (viet 1)) hoc tien duan*.