Perhaps you should try some spelling variations:
relational constraint » selectional constraint, equational constraint, orientational constraint
functions relational » functional relational, functions rational, functions relations
microarray profiling » microrna profiling
array string » array strong, arrays strings, array sharing

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: functions relational constraint programming ((array string) OR (microarray profiling))~.
• Adding a wildcard symbol may retrieve word variants: functions relational constraint programming ((array string) or (microarray profiling))*.