Perhaps you should try some spelling variations:
"public administration" » "publico administration" (Expand Search), "publicas administration" (Expand Search), "publicos administration" (Expand Search), "public administracao" (Expand Search)
"publica administration" » "publicoa administration" (Expand Search), "publicasa administration" (Expand Search), "publicosa administration" (Expand Search), "publica administracao" (Expand Search)
"publicoooa administration" » "publicooooa administration" (Expand Search), "publicasoooa administration" (Expand Search), "publicosoooa administration" (Expand Search), "publicoooa administracao" (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("public administration") OR ("publica administration"))) OR ("publicoooa administration"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"public administration\") OR (\"publica administration\"))) OR (\"publicoooa administration\"))".
• Removing quotes may allow a broader search: (((( public administration ) OR ( publica administration ))) OR ( publicoooa administration )).
• Adding a wildcard symbol may retrieve word variants: (((("public administration") OR ("publica administration"))) OR ("publicoooa administration"))*.