Perhaps you should try some spelling variations:
trinh quan » trinh luat, trinh han
thiet hoat » thien hoat, trien hoat, thiet hai
quang tuan » quang thanh, quang cua
hieu soat » hieu suat, hieu hoat, hieu luat
tuan van » luan van, tran van, tan van
van hieu » cao hieu
luan va » luan van, luat va

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( trinh quan luan va thiet hoat ) or ( tinh quang tuan van hieu soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( trinh quan luan va thiet hoat ) OR ( tinh quang tuan van hieu soat )).
• Adding a wildcard symbol may retrieve word variants: (( trinh quan luan va thiet hoat ) or ( tinh quang tuan van hieu soat ))*.