A Commerce Search Provider that filter on CatalogContentBase instead of EntryContentBase which allows for hits on node content in catalog ui search.

BetterCommerceSearchProvider.cs

using EPiServer.Find;
using EPiServer.Find.Cms;
using EPiServer.Find.Cms.SearchProviders;
using EPiServer.Find.Commerce;
using EPiServer.Find.Framework;
using EPiServer.Find.Framework.UI.Localization;
using EPiServer.Find.Helpers.Text;
using EPiServer.Shell;
using EPiServer.Shell.Search;

namespace MySite
{
    [SearchProvider]
    // Changed first parameter so it accepts CatalogContentBase instead of only EntryContentBase.
    public class BetterCommerceSearchProvider : EnterpriseContentSearchProviderBase<CatalogContentBase, ContentType>
    {
        private static readonly string SearchArea = "Commerce/Catalog";

        public BetterCommerceSearchProvider(LocalizationService localizationService,
            ISiteDefinitionResolver siteDefinitionResolver,
            IContentTypeRepository contentTypeRepository,
            UIDescriptorRegistry uiDescriptorRegistry,
            EditUrlResolver editUrlResolver,
            ServiceAccessor<SiteDefinition> currentSiteDefinition,
            IContentLanguageAccessor languageResolver,
            IUrlResolver urlResolver,
            ITemplateResolver templateResolver,
            IContentRepository contentRepository)
            : base(localizationService, siteDefinitionResolver, contentTypeRepository, uiDescriptorRegistry, editUrlResolver, currentSiteDefinition, languageResolver, urlResolver, templateResolver, contentRepository)
        {
            // set the EditPath function to return the Commerce edit Url instead of CMS one
            EditPath = GetEditPath;
        }

        // Changed first parameter so it accepts CatalogContentBase instead of only EntryContentBase.
        private string GetEditPath(CatalogContentBase entryContent, ContentReference contentLink, string languageName)
        {
            var catalogPath = Paths.ToResource("Commerce", "Catalog");
            if (catalogPath == "/")
            {
                catalogPath = Paths.ToResource("CMS", null);
            }

            if (!string.IsNullOrWhiteSpace(languageName))
            {
                return string.Format("{0}?language={1}#context={2}", catalogPath, languageName, entryContent.GetUri());
            }

            return string.Format("{0}#context={1}", catalogPath, entryContent.GetUri());
        }


        public override string Area
        {
            get { return SearchArea; }
        }


        public override string Category
        {
            get { return Text.Translate("/commerce/searchprovider/product/name"); }
        }


        protected override string IconCssClass => FindContentSearchProviderConstants.PageIconCssClass;


        protected override ITypeSearch<IContentData> GetFieldQuery(string searchQuery, int maxResults)
        {
            // Did some general improvements here, since the base 
            var findQuery = SearchClient.Instance.Search<CatalogContentBase>();

            if (searchQuery.IsNotNullOrEmpty())
            {
                var normalizedQuery = EscapeForQuery(searchQuery);
                findQuery = findQuery.For(searchQuery)
                    .InField(x => x.SearchTitle())
                    .InField(x => x.SearchText())
                    /* You should install the Find Toolbox 
                      (https://github.com/episerver/EPiServer.Labs.Find.Toolbox/tree/master#fuzzymatch-and-wildcardmatch)
                      and add: */
                    // .WildcardMatch()
                    .BoostMatching(x => ((EntryContentBase)x).EscapedQueryableCode().Match(normalizedQuery), 2);


            }
            return findQuery.Take(maxResults);
        }
        

        private string EscapeForQuery(string input)
        {
            if (input == null)
            {
                return null;
            }

            var buffer = new StringBuilder();

            foreach (var c in input)
            {
                // 0-9: [0x30, 0x39], A-Z: [0x41, 0x5A], a-z: [0x61, 0x7A]
                if (c > 'z' || c < '0' || (c > '9' && c < 'A') || (c > 'Z' && c < 'a'))
                {
                    // Non-ascii or non-alphanumeric. Write unicode position in hex instead.
                    buffer.AppendFormat("{0:X}", (int)c);
                }
                else
                {
                    buffer.Append(c);
                }

            }

            return buffer.ToString();
        }
    }
}