ولهذا إذا اشتبهت عليه القبلة فأخبره واحد عنها لا يجوز له التحري
If the qiblah is uncertain and a person reliably informs someone of its direction, one should not substitute one’s own estimation for that report.
Here taḥarrī means arriving at a probable direction from the available signs. The legal example assumes a report that qualifies as evidence; a lesser personal estimate should not displace it.
The point is not that every stranger's unexamined claim must be trusted. It is that a valid source of information precedes private conjecture in the relevant circumstances.