I think you need to index the part that you want have as filter in a separate field and then use facet searches on that one. See this forum answer.
Related topics
| Topic | Replies | Views | Activity | |
|---|---|---|---|---|
| Elastic cannot filter out only some variants without removing all from result | 0 | 434 | May 4, 2021 | |
| 0 results if 1 variant of 5 is excluded from search | 2 | 823 | January 14, 2019 | |
| Search on variant article number no hit | 2 | 813 | July 3, 2019 | |
| Add tag to index for variants | 15 | 864 | July 5, 2019 | |
| Display all or specific variants in product listings (Elasticsearch) | 1 | 739 | February 17, 2021 |