Perhaps you should try some spelling variations:
"trinh duong xuan can kim soat" » "trinh dung xuan can kim soat", "trinh phuong xuan can kim soat", "dinh duong xuan can kim soat", "trinh dong xuan can kim soat", "trinh luong xuan can kim soat", "trinh duong quan can kim soat", "trinh duong xuan cang kim soat", "trinh duong xuan tan kim soat", "trinh duong xuan chanh kim soat", "trinh duong xuan can kiem soat", "trinh duong xuan can kim loai", "trinh duong xuan can kim hoa", "trinh duong xuan chan kim soat", "trinh duong xuan cat kim soat"
"tin dung luan van hieu soat" » "tin dung luan van hieu suat", "tin dung luan van hieu hoat", "tin dung luan van hieu luat", "tin dung luan cao hieu soat", "tinh dung luan van hieu soat", "tin dung quan van hieu soat", "tin dung lan van hieu soat"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("tin dung luan van hieu soat") or ("trinh duong xuan can kim soat"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("tin dung luan van hieu soat") OR ("trinh duong xuan can kim soat")).
• Removing quotes may allow a broader search: (( tin dung luan van hieu soat ) or ( trinh duong xuan can kim soat )).
• Adding a wildcard symbol may retrieve word variants: (("tin dung luan van hieu soat") or ("trinh duong xuan can kim soat"))*.