Preview - 2009 Macbook pro is faster than my 2016 MBP + touchbar

Hi there

I am using to different Macbooks:

1) Macbook Pro 2009

2) Macbook Pro 2016 (a lot more powerful)

I am trying to search things in a PDF document with about 1900 pages. If I search on my 2009 Macbook the search engine needs about 1-2 seconds. Trying this on my 2016 Macbook and preview starts to freeze and needs about 3 minutes for all the results.

How is this possible ? And what would be problem?

Thanks