Perhaps you should try some spelling variations:
"_ corporation technical report series" » "_ corporation technological report series", "_ collaboration technical report series", "_ incorporating technical report series", "_ corporation technical report server", "_ corporate technical report series"
"_ operation technical report series" » "_ operations technical report series", "_ iteration technical report series", "_ operative technical report series", "_ operation technical report server", "_ operating technical report series"
"_ corporation ethical report series" » "_ corporations ethical report series", "_ corporation ethics report series", "_ corporations ethically report series", "_ corporation medical report series", "_ corporation ethical robot series", "_ corporation ethical root series", "_ corporation ethical report server", "_ corporate ethical report series"

Try widening your search to All Fields.

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: (((("_ corporation technical report series") OR ("_ operation technical report series"))) OR ("_ corporation ethical report series")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"_ corporation technical report series\") OR (\"_ operation technical report series\"))) or (\"_ corporation ethical report series\"))".
• Removing quotes may allow a broader search: (((( _ corporation technical report series ) OR ( _ operation technical report series ))) or ( _ corporation ethical report series )).
• Adding a wildcard symbol may retrieve word variants: (((("_ corporation technical report series") OR ("_ operation technical report series"))) or ("_ corporation ethical report series"))*.