You can filter by one classification at a time. It is not possible to combine two (or more) classifications in the same search.
You can search multiple collections at the same time. The search operator for collections is OR. This means that for each collection you add to your filter, you add the items from that collection. The items that appear in the results are therefore either in one collection or the other.
Example:
You are filtering multiple collections
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The results include items found in one of the filtered collections.
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You can search multiple tags at the same time. The search operator for tags is AND. This means that the items that appear in the results must have all of the selected tags.
Example :
You are filtering by multiple tags
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The results include only items that have all the filter tags.
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When you combine different filters, the search operator applied is AND. In other words, for each filter you add to your search, you add an exclusion criterion. The objects that appear as results are therefore those that have all the selected criteria as attributes.
Example :
Combine different filters
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The results include only items that have all the attributes filtered.
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