Perhaps you should try some spelling variations:
purification requirements » verification requirements, certification requirements, gamification requirements
requirements based » requirements a
based excision » base excision, based exclusion, based decision
arrays probing » array probing, rays probing, arrays producing
array string » array strong, arrays strings, array sharing
array using » arrays using

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: purification requirements based excision ((((array using) OR (array string))) OR (arrays probing))~.
• Adding a wildcard symbol may retrieve word variants: purification requirements based excision ((((array using) or (array string))) or (arrays probing))*.