Perhaps you should try some spelling variations:
"nhan dat su chinh tri vien." » "nhan dan su chinh tri vien." (Expand Search), "han dat su chinh tri vien." (Expand Search), "nhan dang su chinh tri vien." (Expand Search), "nhan dat so chinh tri vien." (Expand Search), "nhan dat cua chinh tri vien." (Expand Search), "nhan dat cuu chinh tri vien." (Expand Search), "nhan dat su chinh tai vien." (Expand Search), "nhan dat su chinh tri viet." (Expand Search), "nhan dat su chinh tri chien." (Expand Search)
"nhan vat xu chinh tri kien." » "nhan vat tu chinh tri kien." (Expand Search), "nhan vat nu chinh tri kien." (Expand Search), "nhan vat xu thinh tri kien." (Expand Search), "nhan vat xu chinh trien kien." (Expand Search), "nhan vat xu chinh tri kinh." (Expand Search)

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: (("nhan dat su chinh tri vien.") OR ("nhan vat xu chinh tri kien."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"nhan dat su chinh tri vien.\") OR (\"nhan vat xu chinh tri kien.\"))".
• Removing quotes may allow a broader search: (( nhan dat su chinh tri vien. ) OR ( nhan vat xu chinh tri kien. )).
• Adding a wildcard symbol may retrieve word variants: (("nhan dat su chinh tri vien.") OR ("nhan vat xu chinh tri kien."))*.