Perhaps you should try some spelling variations:
"trinh van quang va kiem soat" » "trinh han quang va kiem soat", "trinh quan quang va kiem soat", "trinh toan quang va kiem soat", "trinh van quan va kiem soat", "trinh tran quang va kiem soat", "trinh van tuan va kiem soat", "trinh van quang va kiem toan", "trinh van quang van kiem soat", "trinh van quang ma kiem soat", "trinh van quang van kien soat"
"trinh dung luan luan hieu lon" » "trinh dung quan luan hieu lon", "trinh dung luan luong hieu lon", "trinh dung luan van hieu lon", "trinh dung luan luan tieu lon", "trinh dung luan luan dieu lon", "trinh dung luan luan thiet lon", "trinh dung luan luan lieu lon", "trinh dung luan luan hieu loi", "trinh dung luan luan hieu buon"

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: (("trinh van quang va kiem soat") or ("trinh dung luan luan hieu lon"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("trinh van quang va kiem soat") OR ("trinh dung luan luan hieu lon")).
• Removing quotes may allow a broader search: (( trinh van quang va kiem soat ) or ( trinh dung luan luan hieu lon )).
• Adding a wildcard symbol may retrieve word variants: (("trinh van quang va kiem soat") or ("trinh dung luan luan hieu lon"))*.