[Koha] Search page don't always show results when it should

Hi, First of all I use Koha 16.0503000 on Debian. Everything works fine but I have one problem. If I do a search, I can see the results but sometime (randomly) when I click on a page number, Koha tells me that he has no results. If I refresh the same page (1 or 2 time, depends) then the results are showed. How can I fix this ? I have two different Koha installations (prod and test) but it's the same problem. I updated my test server to the latest koha version available on apt (16.1105000) and then again, same problem. Thanks. -- Joël M. Administrateur Réseaux/Système. Institut Biblique de Nogent-sur-marne.