You can use the Find command to select a set of topics that contain specific text.
On the Home tab, in the Editing group, click the Find arrow, then click Find.
Enter your text in the Find what box .
Click Find All.
All the topics with matching text will be selected.
The Find command provides additional features for tailoring your search and offers an option to replace the matching text. See Find and replace for more information.
Once the topics are selected you can go on to modify their format (colors, fonts, shapes, etc.), copy them, or remove them from the map. You can also choose to Filter the map or bookmark the topics based on your selection.