Hello,
I do not see the Loco translate plugin on your site. Mentioned strings of the search come from XStore Core plugin. If you are using PoEdit, create a translation for the Core plugin.
About this search there is no a page or static bloc where I can modify textes and add more infos ?
– no.
And where can I change background color of tags ? (For now in red)
– Theme Options > Styling > Main color
Regards