We tried on version 3.7 but on 3.8. The problem is that no items are displayed in any category a. When it clicks on any category, it excludes: We could not find any results for your search ...
Also, search for any keyword does not work.
The rest is all right and the Alpha theme is almost perfect.

How to solve the problem?

Looks like we had to find a problem ourselves.
 
It's not clear why they are not automatically creating the following tables in mysql database?

oc_t_category_alpha
oc_t_item_alpha
oc_t_item_stats_alpha

There are even more problems where your technical service should react quickly ...

@alexborg
Tables should be installed when you activate theme.

Yes, but it was not easy. There is probably a problem communicating with the Osclass database ... if it does not work automatically then there is a problem

@alexborg
It should be automatical

How did they solve? I have the same problem when installing a theme, the theme tables are not created. 

@Matias
Uninstall & install theme again or manually execute content of theme's struct.sql (replacing db placeholders with ones you have in db)