Hii,

You're overriding _send_mail() and returning res, which may be an email template or dict of values, but you're not actually calling message_post, nor guaranteeing the email is sent with the right linkage to log in the chatter.

Here’s how to ensure the email appears in the chatter of the related survey.survey record:

from odoo import models

class YourModel(models.Model):
    _inherit = 'your.model'

    def _send_mail(self, answer):
        res = super()._send_mail(answer)

        survey = self.survey_id

        # Prepare email values
        email_values = {
            'auto_delete': False,
            'model': 'survey.survey',
            'res_id': survey.id,
        }

        # If res is a mail.template:
        if isinstance(res, dict):
            res.update(email_values)
        elif hasattr(res, 'write'):
            res.write(email_values)

        # Optional: Post a message to chatter manually (if not posted automatically)
        survey.message_post(
            body="An email was sent to the user.",
            message_type="notification",
            subtype_xmlid="mail.mt_note",
        )

        return res

i hope it is use full