Perhaps you should try some spelling variations:
specialist librarians » specialist libraries
scientific libraries » specific libraries, scientific theories, science libraries
spectral libraries » several libraries, spectral library, specific libraries
special libraries » several libraries

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: academic & ((((spectral libraries) OR (specialist librarians))) OR (((scientific libraries) OR (special libraries)))).
• Adding a wildcard symbol may retrieve word variants: academic & ((((spectral libraries) or (specialist librarians))) or (((scientific libraries) or (special libraries))))*.