Some file can't be tracked by Commits.QueryBy(path)

I use to following code to track the latest change for a special file. But I found some file can't be tracked while the others can be tracked correctly.

var latestCommitLog = repository.Commits.QueryBy(file);
if (latestCommitLog.Count() > 0)
{
        var latestCommit = latestCommitLog.First().Commit;
}
else 
{
        // no history
        // some file has be pushed to repository but can't be tracked.
}

The issue only identifies repository.Commits.QueryBy(file); first reproduce it with a tracked file that works and one that does not, recording their path details and repository state. Trace that API call to determine why the result is empty. Done means the failing file returns its latest commit, with a regression test covering the case.