Indeed Job Alerts are capped at 30 results per notification. To show all matches for your search – both old and new – click the all jobs link to navigate to our website, which displays all the matches.
If you sort the search results by date, the first matching results are the new jobs mentioned in the email.
Within the email, you also can click view jobs since yesterday. Since you are receiving daily job alerts, choosing since yesterday shows you the newest alerts.