It might be a challenge to find the right 'label' in the translations table. Sometimes translations can be done from the web pages themselves.
In those cases a 'tooltip' will show up when hovering the text:
This example shows that "No results.." was loaded from the translations table. The tootlip tells us that the translation-label is "noResults".
Clicking on "edit" will result in a popup with the translations table. This time only one label is visible.
After translating, the button "Store Translations" wil save the new data.
Clicking "Close" will close the popup without saving.