I am sorry for stupid questions, I just started using Poser again after some years. I still have my Poser 2014 from back then and I am trying to master the simplest operations on it? so maybe I am closer to neanderthals than to modern humans.

I understand that I can convert DAZ stuff to Poser stuff with DSON importer. I heard it is free but i can't find it anywhere! I searched DAZ official website, but had no luck.

Can anybody kindly give a hint where to look for?

Technically, it isn't available anymore since DAZ has decided not to support it.  At present, the DSON Importer cannot successfully convert Genesis 8 to Poser; I might be one of the few able to get that figure into Poser 12.  If you didn't pick it up when it was released then you're out of luck.

IIRC, though DS no longer support DSON, their 'T+C' barred redistribution, reverse engineering etc etc...

Although a tad long-winded, you can export clad figures from DS as rigged FBX which Poser may read.

I managed to get Kalea7 Rogue, a former DS freebie, into Poser thus...

https://www.renderosity.com/gallery/items/3103742/ds-kalea-7-rogue-ported-to-poser-as-fbx-yay

FWIW, I routinely port DS props to OBJ+MTL for use in Poser. DSF Tools ($$) is now un-supported, and seems to hang on DSF files above ~1 MB. YMMV.
DS' UI gives me a prompt migraine, but its Poser-scaled 'OBJ+MTL' export path has no problems with even '>> 10 MB' files.

https://www.deviantart.com/nik-2213/art/Porting-DAZ-Studio-props-to-Poser-friendly-OBJ-MTL-911478576

The DSON installers (32-bit, 64-bit, Mac and Windows) are hard work to find now, but still install and run if you have the correct version of Poser. Only for auto-importing Genesis 1 and 2 figures, or course. Possibly Poser 2014 will need an earlier version of DSON.

If all you want is "artist's reference" done in Poser's Comic Book, then ShareCG has a streamlined free Daz to .OBJ system for free. Can optionally include poly-reduction, to make the figure more weildy in the Poser viewport. Search ShareCG for "Automatic OBJ Exporter".

Thank you for your kind answers. I hoped there was an old version of dson  lying somewhere. I am using Windows 7 with Poser 2014 and I wouldn't want to try any new staff, just get some props form daz to clothify them and use on my characters.

I've had another look and I think I may have misled you on availability. A set of Windows .exe and Mac installers used to be on GitHub, and they've now gone and the WayBack machine didn't get the files (only the Web page). DSON doesn't appear to be publicly available elsewhere.