How can I make a search engine in native reply using asyncstorage in a listview?

The code I have is the following:

Buscador(text) {
    const dataSource = this.state.ds.cloneWithRows(this.state.cars);

    const newData = dataSource.filter(function (item) {

        const itemData = item.desc_producto.toUpperCase()
        const textData = text.toUpperCase()
        return itemData.indexOf(textData) > -1
    })
    this.setState({
        dataSource: this.state.dataSource.cloneWithRows(newData),
        text: text
    })
}

but it gives me error regarding the data source.