Rules for Library fields - Project, Group, Type, Member

If the cursor is in the Project field, the other fields are not used as part of the data set name search and are erased.
If the cursor is in a Group field, the project name and type name (if any) are added to create the search pattern. Each group name is used only once, even if there are many types in that group. As each group name is displayed, the first type name found for that project.group combination is also retrieved. The member name, if any, is not used and is erased.
If the cursor is in the Type field, the project and first group name are used to create the pattern. The Type field is updated and the member name is erased.
If the cursor is in the Member field, the project, first group, and type are used as the data set name. The second, third, and fourth groups are not used.