@zhe, to chime in, you can definitely use Manually Curate Exposures as suggested by @leetleyang, and you could also load your dataset into cryoSPARC Live and use the Overview Tab to view individual exposures and reject them manually and/or using threshold criteria: https://guide.cryosparc.com/live/new-live-session-start-to-finish-guide#4.-exclude-poor-quality-exposures-from-downstream-processing
(Scroll to 4. Exclude Poor Quality Exposures from Downstream Processing)
Once satisfied with your selection, you can Export Exposures (https://guide.cryosparc.com/live/new-live-session-start-to-finish-guide#export-exposures-and-or-particles) and this will make the accepted and rejected exposure outputs available in the corresponding Project in your regular cryoSPARC interface for use in downstream processing.