The first screen-shot shows an analog input (ai) record, which reads its input (INP) directly from a device support module that happens to understand the input description "adm606m....".
The second screen-shot shows a more interesting hierarchy: A binary input record (bi) reads from a calculation (calc), whose first input (INPA) reads from an mbbi which in turn reads from another calc and so on. Note how the color-coding indicates severities.
This tool uses the EPICS network protocol, Channel Access, to read PVs. There is no way to query EPICS V3 IOCs for their database information to determine the available "input" links.
The knowledge of which links to follow for each record type is therefore configured into the EPICS PV Tree application. It is at this time not configurable by end users, but people with access to the source code can determine the syntax from the preferences.ini file and override in the CSS plugin_customization.ini for site-specific settings.