Add Entry to Keyword Field in Workflow

While executing multiple checks in an workflow i would like to add some values (i.e. different Errors/Warning Text) to a keyword variable. is that possible and how?
 

When You edit a keyword variable in a data assignment activity, there is a checkbox which in German says 'Ersetzen' (I guess it says 'Replace in an English system?) which is checked by default.
With this, You tell the Workflow manager not to replace the complete content of the keword field with the right side of of Your assignment, but to append to it.

Be wary of separation characters in whatever Your new value is, see here:
https://support.docuware.com/de-de/knowledgebase/article/KBA-36107

 

Just to be completely sure. So in my case i have to deselect the option "replace". After doing so, the new string will be concatenated to the existing entrys in the keyword field?

Yup!