Hello, As with other fields of type List, you can filter reporting results by LabelIds using CONTAINS_ANY, CONTAINS_ALL, or CONTAINS_NONE. You could check the guide on labels for more clarity. Please see a sample AWQL below :
SELECT CampaignId, LabelIds, Labels FROM CAMPAIGN_PERFORMANCE_REPORT WHERE Labels CONTAINS_ANY [926238056]
Let me know if you have any additional questions.
Thanks,
Sreelakshmi, AdWords API Team