Recently published Editions don't show up on Google Scholar

OJS Version

Current version

2.4.8.1 (September 20, 2016 - 03:41 PM)

OS platform Linux
PHP version 5.6.40
Apache version Not available
Database driver mysql
Database server version 5.6.44

Mart, April and May Editions don’t show up on Google Scholar.
Any thoughts on this issue???