I am having a similar problem as this past one from another user:
“In my site I have the “Advanced Custom Field” plugin, with different fields, three like radio and two like checkbox. Now, with your plugin, in the search-form, I connected the Post-meta fields with the custom fields. It seems that the search doesn’t find the meta-data of the checkbox fields (not results), but It works just with the meta-data of the radio custom fields. It’s because ACF inserts the checkbox fields data in an array? There is a solution?”
My custom field name has no typo problems, as the suggested solution asked.
Do you have a solution?? I really wanted to be able to search some multiple options of my custom fields. I have one like “atractions” and then each post might have more than one, and I would like the user to search more than one too. The ACF with single values work, this multiple ones that always returns “no results found”, even if I do have then set.