When will the parameter "Find Users by Any Name Query" be used?

The same question was posted to me but I have no idea, so I have to rely on the wisdom of the community.

In the JTS LDAP configuration (advanced properties), there is a parameter called "Find Users by Name Query", and I can verify that it is used when we do Import Users. And there is another parameter called "Find Users by Any Name Query" with the default value "(| (cn= ?1) (cn=_?1))". Does anybody know when the latter will be used?

I'm  using CLM 6.0.2 if that matters.