Here's how you can delete apps from your download history in the Google Play store.
1. Go to the My Apps section in the Google Play store.
2. Tap the All tab.
3. Tap the "x" next to the app you want to delete.
4. Confirm that you want to delete the app and remove it from your download history.
For more, see the original article at the link below.
Delete App History in the Android Play Store | Lifehacker