If you're not seeing an app on the Aurora Store is because you're most likely using the "anonymous login" feature which provides you with a disposable account to use the store. You may not see apps relevant to your country, but rather the country of the account being provided to you.
To work around this, you can make Aurora Store open Play Store links, and then do a search for the app and open it, which will open it in Aurora Store.
If you have Play Store installed, you will need to remove its ability to open Play Store links, so that you can grant that to Aurora Store.
The settings for this can be found at Settings > Apps > select the relevant app > Open by default > Add link.
I hope that helps.