You want to add multiple values to a smart list filter as described here: https://docs.marketo.com/display/public/DOCS/Add+Multiple+Values+to+a+Smart+List+Filter . However, when you go to do so for a field that has a type of "Text" you are not able to add multiple values.
This is expected behavior for Marketo Text fields. As a workaround, you can add the same filter to the smart list multiple times for each value you want included.
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