Are you using Dynamics 365 Business Central on-premise and are you obtaining this error message when searching on a list?
This is because your applied filters are returning a query result set with a too long execution time.
With Dynamics 365 Business Central on-premise there’s a “not so well known” setting on the Database tab in the Business Central Server Administration tool called SearchTimeout.
This setting specifies the time (in seconds) that a search operation on lists in the client will continue until it is terminated. When the limit is reached, the message you can see in the above picture is displayed in the client.
If needed, in the on-premise world you can increase this limit (via Server Administration or directly from Powershell) and in this way you can enable longest queries. Not so recommended, but sometimes it could be useful to change it.