@classmethod
def textSearch(cls, text, limit, skip, query=None, sort=None, db=None, **kwargs
    ):
    """Find by text search and return all matched instances.

        args:
            search text(str):
            limit(int):
            skip (int):
            query(dict):
            sort (int): condition other than text search
        """
    __db = db if db else cls.__db
    if not query:
        query = {}
    if cls.__search_text_index_unit__ == 'bigram':
        query['$text'] = {'$search': cls.generateSearchBiGramStr(text)}
    else:
        raise Exception('index unit must be either bigram or morpheme')
    if not sort:
        sort = [('score', {'$meta': 'textScore'})]
    cursor = __db[cls.__collection__].find(query, {'score': {'$meta':
        'textScore'}}, **kwargs).skip(skip).limit(limit)
    print(f'B : {cursor}')
    cursorResults = cursor.sort(sort)
    return list(cls.generateInstances(cursorResults))
