diff --git a/src/messenger/webim/operator/history.php b/src/messenger/webim/operator/history.php
index 1b3efaa4..950f3565 100644
--- a/src/messenger/webim/operator/history.php
+++ b/src/messenger/webim/operator/history.php
@@ -58,8 +58,10 @@ if ($query !== false) {
 		$searchConditions[] = "({chatmessage}.tmessage LIKE :query" .
 					($searchInSystemMessages?'':" AND ({chatmessage}.ikind = :kind_user OR {chatmessage}.ikind = :kind_agent)") .
 					")";
-		$values[':kind_user'] = Thread::KIND_USER;
-		$values[':kind_agent'] = Thread::KIND_AGENT;
+		if (! $searchInSystemMessages) {
+			$values[':kind_user'] = Thread::KIND_USER;
+			$values[':kind_agent'] = Thread::KIND_AGENT;
+		}
 	}
 	if ($searchType == 'operator' || $searchType == 'all') {
 		$searchConditions[] = "({chatthread}.agentName LIKE :query)";