You can customize the tags displayed in the Resource ManagerInsert option using the following persistent user preference:

For the optional doctype token, you can specify a specific document type base name (for example, ditabase or bookmap). If omitted, the preference applies for all document types that do not have an explicit preference value set.

For the optional tab token, you can specify the same values as those used to set the default tabs. If omitted, the preference applies for all tabs.

The value of the preference is a list of tag names, separated by commas. As the cursor moves around the document, the Resource Manager scans this list until it finds the tags that are legal at the current location and displays only those tags in the Insert option.

For example, you could use the following ACL code to just display topicset or topicsetref tags in Insert option for DITA BookMaps: