Comparing strings, ignoring case, punctuation, and whitespace
You might want to create a combined CharacterSet of punctuation and whitespace first and then apply this set using a single operation. This should speed things up. Please have a look at this code snippet:

let punctuation = CharacterSet.punctuationCharacters
let whitespace = CharacterSet.whitespaces
let unwanted = punctuation.union(whitespace)
let components = filterString.components(separatedBy: unwanted).joined(" ")
let filterStringContainsSearchText = components.contains(searchText)