Perhaps you should try some spelling variations:
trinh luan » trinh luat, trinh quan, trinh han
nhung cong » dung cong, thong cong, hang cong
doi chieu » doi chi, ho chieu, mot chieu
doc hieu » toc thieu, hoc thieu, hoc hien
tinh cua » trinh cua, sinh cua, tinh chat
cong anh » cong danh, dong anh, hong anh
tuan tai » toan tai, quan tai, tan tai

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) tinh - hanh ((trinh luan) OR (tinh cua)) nhung cong anh tuan tai~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doc hieu)) tinh - hanh ((trinh luan) or (tinh cua)) nhung cong anh tuan tai~".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (doc hieu)) tinh - hanh ((trinh luan) or (tinh cua)) nhung cong anh tuan tai*.