Why is this an issue?
Conditions using "Contains" or "Not Contains" can cause performance issues on an instance. This is because for the contains filter, the search tool needs to read the entire content of all records searched to find a solution which makes this action heavier for the instance.
You can also face problems with security or wrong collection of information, as there is no guarantee that "Contains" will bring you exactly what you need, in 100% of calls.
Best practices
Re-write the report conditions to use a better filter if possible.