If this is the case, could you guide me which part of the code I can update to load the result using "AND" conditions?
I have breifly went thorugh the code and noticed that the queries are located in the ResultModel. Then I updated the code to check for $this->filtersCollection. If it equals to 'Tags', I modified the $whereCondition. However, it shows no results.
$whereCondition = $this->_db->quoteName(
$valueItemTableAlias . '.' . $valueItemRefConfig->getValueId()->getDbColumn()
) . ' IN (' . implode(',', $query->bindArray($filter->getRequest(), $dbParamDataType)) . ')';
$subQuery2 = $this->_db->getQuery(true);
$subQuery2->select($this->_db->quoteName('content_item_id'))
->from($this->_db->quoteName('#__contentitem_tag_map'))
->where($this->_db->quoteName('tag_id') . 'IN (' . implode(',', $query->bindArray($filter->getRequest(), $dbParamDataType)) . ')')
->group($this->_db->quoteName('content_item_id'));
$whereCondition = '(' . $whereCondition . ' AND ' . $this->_db->quoteName(
$valueItemTableAlias . '.' . $valueItemRefConfig->getValueId()->getDbColumn()
) . ' IN (' . (string)$subQuery2 . '))';