Building on Amit's reply, IMHO it's unlikely to be a leading space because the text is flush left. If any of the Yes entries was preceded by a space it would be visibly shown as an indent from the left cell wall.
However, as he suggested, the same result is caused if the Yes entry is followed by one or more spaces, but the test formula he supplied would not indicate it - you'd also have to do the same but with the * wildcard behind the word Yes. What happens
if you just carefully re-enter one of the Yes values?
If these responses don't help resolve the issue, or if it is evident in scenarios other than this example, please be certain to indicate your present version level of Office 2016 & your flavor of macOS, along with any additional descriptive details & examples
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