Keyword Search on job listings not working

**Describe the bug**
I have about 100 job listings on our Job Manager page (https://www.boardroommagazine.com/jobs/) but the keyword search results in "There are no listings matching your search." It's the same no matter what I put in the keyword input. Category and Location searches work fine.

**To Reproduce**
Steps to reproduce the behavior:
1. Go to 'https://www.boardroommagazine.com/jobs/'
2. Enter any keyword from any of the listings
3. Click "Search Jobs"
4. result: "There are no listings matching your search."

**Screenshots**
https://www.boardroommagazine.com/wp-content/uploads/2026/01/CleanShot-2026-01-27-at-12.36.15@2x.png

**Expected behavior**
Matching jobs should appear, but none are found.

**Isolating the problem (mark completed items with an [x]):**
- [ ] I have deactivated other plugins and confirmed this bug occurs when only WP Job Manager plugin is active.
- [ ] This bug happens with a default WordPress theme active.
- [ X] I can reproduce this bug consistently using the steps above.

**WordPress Environment**
- WordPress Version: 6.0
- WP Job Manager Version: 2.4.0
- PHP Version: 8.2.30
- Other important details:

Start by reproducing the failure at https://www.boardroommagazine.com/jobs/ with the stated WordPress 6.0, WP Job Manager 2.4.0, and PHP 8.2.30 environment, then compare keyword searches with the working category and location searches. Done means keywords from existing listings return matching jobs instead of the no-results message.

Written by the indexing model from the issue text.