Is it possible ...

You can go in the config under the display tab and change the option "After a product is added to the cart" to "stay and display a popup notice"

You can edit the notice popup following this post instructions:
www.hikashop.com/fr/support/forum/4-how-...ng-address.html#4578

Indeed, only the product name and product description are used for the search plugin.

If you want to add the keywords in the search, you should edit the file plugins/search/hikashop_products.php and
after the line:
$filters[] = "a.product_description LIKE ".$text;
add a line:
$filters[] = "a.product_keywords LIKE ".$text;

and change the code:
$wordFilters = array();
$subWordFilters1 = array();
$subWordFilters2 = array();
$wordFilters2 = array();
foreach ($words as $word) {
$word = $db->Quote( '%'.$db->getEscaped( $word, true ).'%', false );
$subWordFilters1[] = "a.product_name LIKE ".$word;
$subWordFilters2[] = "a.product_description LIKE ".$word;
if($multi){
$wordFilters2[] = "b.value LIKE ".$word;
}
}
$wordFilters[0]= '(' .implode( ($phrase == 'all' ? ') AND (' : ')
OR ('),$subWordFilters1). ')';
$wordFilters[1]= '(' .implode( ($phrase == 'all' ? ') AND (' : ')
OR ('),$subWordFilters2). ')';
$filters[] = '(' . implode( ') OR (', $wordFilters ) . ')';
if($multi){
$filters2[] = '(' . implode( ($phrase == 'all' ? ') AND (' : ')
OR ('), $wordFilters2 ) . ')';
}

to:
$wordFilters = array();
$subWordFilters1 = array();
$subWordFilters2 = array();
$subWordFilters3 = array();
$wordFilters2 = array();
foreach ($words as $word) {
$word = $db->Quote( '%'.$db->getEscaped( $word, true ).'%', false );
$subWordFilters1[] = "a.product_name LIKE ".$word;
$subWordFilters2[] = "a.product_description LIKE ".$word;
$subWordFilters3[] = "a.product_keywords LIKE ".$word;
if($multi){
$wordFilters2[] = "b.value LIKE ".$word;
}
}
$wordFilters[0]= '(' .implode( ($phrase == 'all' ? ') AND (' : ')
OR ('),$subWordFilters1). ')';
$wordFilters[1]= '(' .implode( ($phrase == 'all' ? ') AND (' : ')
OR ('),$subWordFilters2). ')';
$wordFilters[2]= '(' .implode( ($phrase == 'all' ? ') AND (' : ')
OR ('),$subWordFilters3). ')';
$filters[] = '(' . implode( ') OR (', $wordFilters ) . ')';
if($multi){
$filters2[] = '(' . implode( ($phrase == 'all' ? ') AND (' : ')
OR ('), $wordFilters2 ) . ')';
}


The problem is that the more fields we add in the search and the longer the queries will take. We need to look at a better solution in the future...