You are using WordPress to host your website. Some post previews show a hyperlink ">> Read more…" but others have no hyperlink. Some post previews (e.g., when you search the website for a pattern) are not updating. Older versions of the post are previewing. How do you get the ">> Read more…" hyperlink to show in the preview and how do you get the post to be up-to-date?
Try copying the content of the old posting and posting it again. With new postings we cannot reproduce the problem.