QGIS select multiple features by value

I have a polygon layer and every polygon has a unique gml_id. I want to select multiple at the same time. Normaly I use selection by expression and it works very well. I fount the tool select by value and wonder how it works to select multiple features.

Different inputs that doesn’t work

I´ve tried different spellings in the input mask, but it doesn’t work.
What is the correct synthax?

This is my "select by expression"

I use the QGIS Version 3.4.8 LTR