I appreciate your time posting here, queenie-santoc.

For now, you can follow these steps to search for the application that you want to integrate with QuickBooks Online:

1. Go to this link: Choose your country.
2. Find and select your country.
3. In the QuickBooks Online homepage, click the Small Business menu located at the top.
4. Choose Apps & Add-Ons.
5. Search and select the application to see the overview.

You can also reach out to third-party's support team for the integration process. 

Please let me know if there's anything else you need with QuickBooks Online. I'd be more than happy to help.