Should I be able to highlight any type of text in iBooks and/or google docs off my iPad Pro?

[iMore Question]

I am able to see my documents in both iBooks and google docs but I can't get the highlighting to work. When I touch the screen I don't get the option.

 

[Larry Cook1]

I just went into iBook and opened a book. I tapped on a word and was able to highlight as usual. I didn't hold down I just tapped.