Hello Orestis,
When searching in the Performance View, you can filter the view by searching for numbers that start with any number of characters. For instance, if you entered 123, 12, or 12345, you would see matches for any numbers that started with those digits. However, we do not filter numbers based on digits in the middle of the DNIS. I was able to find this idea in the Product Ideas Lab that seems to match what you're looking for. I would highly recommend voting and commenting on the idea so that our Product team knows that you would like to see this feature.
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Jason Kleitz
Online Community Manager/Moderator
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