Be sure that STRFLG is set to 1 in KEYWORD>DATABASE>EXTENT_BINARY in order to output strain data to ELOUT.
Furthermore, you may open the d3plot in LS Pre-Post, then navigate to the 'Post' tab, and view specific element history for maximum principal strain. If you'd like to see all of the elements in the model, you can also use the ASCII tab. and select 'All' elements which were in the element set that was used in the HISTORY set.