Try your search with a different keyword or use * as a wildcard.
@model QueuedEmailSearchModel
@{
//page title
ViewBag.PageTitle = T("Admin.System.QueuedEmails").Text;
//active menu item (system name)
NopHtml.SetActiveMenuItemSystemName("Queued emails");
}
@{
const string hideSearchBlockAttributeName = "QueuedEmailsPage.HideSearchBlock";
var hideSearchBlock = await genericAttributeService.GetAttributeAsync(await workContext.GetCurrentCustomerAsync(), hideSearchBlockAttributeName);
}