Can we add an extra explanation in the specific objective of each Work Package besides what is already specified in the Result Amplification Strategy ?

You may use the 250 characters available to describe your SOs in the way that seems most relevant for you. Making the connection to the RAS and showing that they are realistic and achievable by the end of the project, specific and measurable. The field dedicated to the Work Package description gives also the possibility to further detail the way you will implement each specific objective.