Perhaps you should try some spelling variations:
irrigation requirements » irrigation equipment, nutrition requirements
requirements a » requirements _
array imaging » arrays imaging, airway imaging, ray imaging
array string » array strong, arrays strings, array sharing
a dimension » _ dimension, new dimension

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• Performing a fuzzy search may retrieve terms with similar spellings: irrigation requirements a dimension ((array string) or (array imaging))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: irrigation requirements a dimension ((array string) OR (array imaging)).
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