Update documentation of attribute searchpath in UserManual.md

UserManual.md

@@ -1134,7 +1134,7 @@ For example :
 
 #### searchpath attribute: ####
 
-The `searchpath` attribute allows searching for a file name using the `PATH` environment variable. The attribute defines a file name (including the file extension) to search in the list of directories identified in the `PATH` environment variable. If the given file name cannot be found in a PATH directory, the action execution stop and reports an error.
+The `searchpath` attribute allows searching for a file name using the `PATH` environment variable. The attribute defines a file name (including the file extension) to search in the list of directories identified in the `PATH` environment variable. If the file can be found in multiple PATH directories, the first match is used to set the property. If the given file name cannot be found in a PATH directory, the action execution stop and reports an error.
 
 For example, the following sets the property `python.exe.path` to the location of the python interpreter :
 ```xml