Example code that fixes common misspellings of words in seaches. Parameterize to taste 👍

wp-fix-search-typos.php

<?php

add_action( 'pre_get_posts', function( $query ) {
    if ( !$query->is_main_query() || !$query->is_search() ) {
        return $query;
    }

    $common_misspellings = [
        'lorem' => ['lorum', 'lorm', 'lormu', 'lormum', 'lormum'],
        'ipsum' => ['ipusm', 'ipsums', 'ipsumz', 'ipsumz', 'ispum'],
        'dolor' => ['dolr', 'dolro', 'dloro', 'doolr'],
    ];

    $search_synonyms = [];
    foreach ( $common_misspellings as $intended => $typos ) {
        foreach ( $typos as $typo ) {
            $search_synonyms[ $typo ] = $intended;
        }
    }

    $search = $query->get( 's' );
    $search_parts = explode(' ', $search);

    $reworked_search = [];
    foreach ( $search_parts as $search_part ) {
        $search_part = trim( $search_part );
        if ( !empty( $search_part ) && isset( $search_synonyms[ $search_part ] ) ) {
            $search_part = $search_synonyms[ $search_part ];
        }

        $reworked_search[] = $search_part;
    }
    $query->set( 's', join(' ', $reworked_search) );
});