There are several User Permissions related to Find Unapplied Credits (Transactions menu) and the various options available.
Go to Tools > Manage Users & Permissions > User IDs (click on a UserID) > User Permissions (left) to set the permissions.
Note: If a User is logged in when changes are made to their permissions, they'll have to log out and then back in before the changes will take effect.
These are the permissions related to Find Unapplied Credits (Search for Credit Transactions & Apply Credits):
|Find Unapplied Credits, Mass Edit Transactions
|Transaction Advanced Search
|View Family Page
See Permissions for Jackrabbit Users for more information.