diff --git a/app/vmselect/promql/eval.go b/app/vmselect/promql/eval.go
index 962d98c6d..f13a9b7d5 100644
--- a/app/vmselect/promql/eval.go
+++ b/app/vmselect/promql/eval.go
@@ -285,10 +285,10 @@ func evalExpr(ec *EvalConfig, e metricsql.Expr) ([]*timeseries, error) {
 		var tssLeft, tssRight []*timeseries
 		switch strings.ToLower(be.Op) {
 		case "and", "if":
-			// Fetch right-side series at first, since the left side of `and` and `if` operator
-			// usually contains lower number of time series. This should produce more specific label filters
-			// for the left side of the query. This, in turn, should reduce the time to select series
-			// for the left side of the query.
+			// Fetch right-side series at first, since it usually contains
+			// lower number of time series for `and` and `if` operator.
+			// This should produce more specific label filters for the left side of the query.
+			// This, in turn, should reduce the time to select series for the left side of the query.
 			tssRight, tssLeft, err = execBinaryOpArgs(ec, be.Right, be.Left, be)
 		default:
 			tssLeft, tssRight, err = execBinaryOpArgs(ec, be.Left, be.Right, be)