problem on blog page

Hello. I noticed such a thing:

If you are on any page of posts (blog), for example this one is https://oashop.ru/2018/10/13/skrab-dlya-gub-opisanie-sredstva-i-pravila-ispolzovaniya/

And when you enter some query into the product search bar, for example – “scrubs”, then the link of the post itself is displayed in the drop-down list of goods, and the value is added to it – [object Object], and the link takes the form – https://oashop.ru/2018/10/13/skrab-dlya-gub-opisanie-sredstva-i-pravila-ispolzovaniya/%5Bobject%20Object%5D, and accordingly, when you click on them, you go to page 404 … link post is duplicated, also with an incomprehensible meaning …

What could it be? On other pages and from mobile devices I do not observe this problem …

I wrote a theme developer, he looked at my site, then we found the reason for this error, your plugin, how can I fix this? Thanks for your help!

The page I need help with: [log in to see the link]