Perhaps you should try some spelling variations:
introduction case » introduction ch, introduction chap, introduction chapter
array profiling » array processing, microarray profiling
case density » clause density, based density, scale density
array arcing » array forming, array probing, array sharing
array string » array strong, arrays strings, array sharing

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

• Performing a fuzzy search may retrieve terms with similar spellings: general introduction case density ((((array arcing) or (array profiling))) or (array string))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: general introduction case density ((((array arcing) OR (array profiling))) OR (array string)).
• Adding a wildcard symbol may retrieve word variants: general introduction case density ((((array arcing) or (array profiling))) or (array string))*.