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The "comparison" is a Contains function, ie the filter will return any assets, whose "free text string" contains the parameter, eg a parameter of "flower" will return the asset. The parameter "flo" will not return the asset. However, the parameter "flo*" will return the asset; as will the parameter "*wer".
Due to the inner workings of how such filters work, any search, which has a freetext filter, MUST be populated (see UseSolr for a guide on how to populate a search).
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