Removing only existing images after pipeline build

Change-Id: I5c242bcaea68bb4fa5bca7231975ddc4086a8d53
diff --git a/Jenkinsfile b/Jenkinsfile
index d11c4c5..3036c3a 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -42,7 +42,9 @@
                 stage 'Clean'
                 sh 'docker stop xos-gui'
                 sh 'docker rm xos-gui'
-                sh 'docker rmi -f $(docker images -aq)'
+                sh 'docker rmi -f xosproject/xos-gui:latest'
+                sh 'docker rmi -f nginx:candidate'
+                sh 'docker rmi -f nginx:latest'
             }
             echo "RESULT: ${currentBuild.result}"
        }