Hi ONGC Limited,
Few things here - First as you are probably already aware by now, 12.5 has been end of life for quite some time now and we no longer support that version. We would suggest that you upgrade to 14.1 when possible so that we can support your installation.
Second, this problem is typically caused by custom list forms. If you rename the site\mods\www\htmpl folder and then run pdm_webcache, then clear your browser cache, and log into SDM to try the same search, does it then show the correct object? If so, then it has to do with your custom forms, and you will have to look into the custom code that you have added to the forms to figure out which piece of code is causing the issue.
Hope this helps,
Jon I.