After some digging in docs I was able to do it that way (specific tag here is "homepage")
`
$searchobject = new SearchEngine();
$searchstring=Array("homepage");
$homepages=$searchobject->searchFieldsAndTags($searchstring, "zenpage_pages", "tags");
foreach($homepages as $homepage) {
zenpage_setup_page($homepage[titlelink]);
`
etc.
So the question is probably closed. Is it the best way to do it or I missed something here?
Thanks