Hi,
First you need to subscribe LMS server to Syslog Collector so that LMS should know that it need to collect the Syslogs from the devices.
You can configure it from
Admin > Collection Settings: Syslog > Syslog Collector > Enter the Ip address of the LMS server
After successfully subscribing to Syslog Collector , you need to make sure that your devices should be sending the Syslog to the LMS server and you can verify the same by looking at the Syslog.log file that exist at location CSCOpx\log directory of the LMS server .
Then go the Reports tab at the top and generate the Syslog reports for your devices.
Kindly refer to the below link to understand the basic requirements to configure Syslog in LMS and the functioning of the Syslog in LMS
http://www.cisco.com/en/US/docs/net_mgmt/ciscoworks_resource_manager_essentials/4.3/user/guide/syslog.html
Many Thanks,
Gaganjeet