The entity filter in alert details should work for the shortened name, or the actual entity name.

[vetinari]

The entity name in the 2nd column might be a shortened one, e. g. pod-zmon-worker-abcdef1234-asdf-default[123:c]. The "filter entries" filters by the full entity name (in this exampe it may be something like pod-zmon-worker-abcdef1234-asdf-default[aws:123456789123:eu-central-1]). Searching for 123:c as you see it in the result table results in no results, but with 123:e you get a result.