So I have a Wordpress site with around 1500 pages. When wanting to create a custom menu (/wp-admin/nav-menus.php), you luckily can search through the pages.

Lets say I want to include the page "My contact page", the search options does not find this page (although it really exists). I found a script on Stackoverflow which expends the search results from 10 to 100. But even then I'm not finding the page.

This problem doesn't count for all the pages, because if I would search for "My portfolio" it can find the page.

Does anyone else have this problem or knows how to fix it? Some pages can be found, others not...