For single- and multi-select custom fields, filter for entities matching specific values. This query parameter can be supplied multiple times, as custom field ID UUID and custom field value ID UUID pairs, separated by a colon :, e.g. &customField=fb9e852c-eb2a-4dd0-81f4-7af266c335d1:7b6e39bb-28bb-46ae-be8a-5c01bbacf78c. Supplying multiple custom field UUID's matches all (AND), and mutliple custom field value UUID's per the same repeated custom field matches any (OR).