There are several options to explore this kind of information.
First of all, you may want to list them for one or several applications

Option 1: for a given application and a specific item type

This option includes more manipulations than the second one,
but allows to narrow down the search to more specific details.

VE7 projects can include several applications.
Each application is listed under the section "Applications" of the treeview

When selecting a given application, you can execute the macro "All PowerBuilder Objects":
A list of item types and their number of occurrences is listed

Down in this list, you can select the Tab control and execute the macro "All items":
All tab controls used in this application will be listed:

CAUTION: only native tab controls used in the application are listed,
userobjects inheriting from this control are not.

If you wish to list the use of a particular userobject inheriting from the tab control:
* in the list mentioned above, select "UserObject" and execute "all items",

* go down the userobjects list and select the one that you're interested in ("u_tab" in the example below)
* execute the macro "Impact analysis" on this user object:
all descendants and/or instances of this userobject are listed with their respective containers

Option 2 : comprehensive search for an entire VE project

This option includes less manipulations than the first one,
and it takes into account :

• all the applications included in the VE project.
• all use of a given native object/control,
• all use of objects/controls inherited from this item

In the treeview, select "PowerBuilder System Objects" under the section "Application"
Execute the macro "Show PowerBuilder Object Hierarchy"
Select the item you're interested in, or search it with the local search (field on top of the treeview).
Execute the macro 'Impact analysis"
Below is an example with the system item "tab":