You probably mean a pattern like this

//*[contains(., '  ')]
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But the result is correct: There is enough whitespace before the <b> tag, for example. You said you wanted multiple spaces between words, so you have to add the "between words" part. I think it is not possible in XPath 1, but as XML::XSH2 was mentioned, you can use it like this:

ls //*[xsh:matches(text(),'\b  +\b')]
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