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Instead of asset, you can indicate the specific nature you are looking for. For example, /api/rest/dam/image
searches for images among all the libraries. Use the name of the nature (only root), which you can get by api/rest/dam/data/assetnature?props=name&lang=en&query={primarytype: {e:null}}.
Other examples:
/api/rest/dam/video
/api/rest/dam/document
/api/rest/dam/3d%20models
/api/rest/dam/print
/api/rest/dam/archive
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Accessing children
If a resource type has a multiple link property, we can get the resources linked to a resource directly without asking the main resource.
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