My iOS app is not shown on App Store, when I search for one of the keywords given. In one of the forum questions it was asked to check https://forums.developer.apple.com/message/370031#370031
For some keyword combinations the app is shown, but not for direct keywords which were separated by comma.
You might try logging in via ASC and see if they've been modified there.
Otherwise, keep in mind that just because a search doesn't immediatelly hit on your app doesn't mean it wasn't in the full list of hits. Frequently, a given app is buried so far down it makes it difficult to know.