If you have dynamic data sources set up for Dropdown or Searchbox elements, and you aren't seeing all of the expected data in your app's run-mode, you'll want to check out your app's Privacy Rules. It's likely that the data type, or one of its fields used as a constraint for the data source, can't be evaluated in run-mode because of Privacy Rules.
To resolve this, you'll want to navigate to your app's Data tab, into the Data Types subtab, and select the impacted data type. From here, you'll want to modify the Privacy Rules for the selected Data Type so that it shows up as expected in your app's run-mode.
For more information on Privacy Rules, check out our manual entry here.