Hi Praj22, 

You can use the field 'Task Name' .

@a_frodsham 

There is no field called Task name. Title gives-> task titles and Name also dont give related content. 

Finally i achieved tis requirement by querying the main list. I extracted ID of list item from Workflow task list's Related content and query main list to get the title of the item and generated below email to send notification to all the pending task approvers. I used https://community.nintex.com/t5/Community-blogs/Send-grouped-notification-based-on-list-items/ba-p/82143 this post to get all tasks in group and send consolidated notification to the assigned to field.

Wf steps:

1. Get item id inside collection using regular expression.

2. Get item id in number variable.

3. Finally query list to get the title or any other field needed.