Splunk is all about time series data, so you can search data/events using various times etc, so what this means, you need to ensure you have well formatted logs with a time stamp, which is what Splunk loves and try's to break the events based on the timestamp.
Splunk has the capability to auto detect most common log formats and timestamps, but this is not best practice for custom logs, its better to ensure you parse and format the timestamp correctly.
As you have a custom log file it looks , you will need to create a new sourcetype for it and apply props and transforms configuration to it, which will then parse and ensure the time stamp is correct.
First try and understand the props concepts and apply that to your log file, it will requires some props code trial and error, until your get it to work as expected.
Start here:
https://lantern.splunk.com/Splunk_Platform/Product_Tips/Data_Management/Improving_data_onboarding_wi...
