[JessicaJohansson]

How many types of crawler available in google search engine ?

[Alexa]

Maybe you may learn about it here: https://developers.google.com/search/docs/crawling-indexing/overview-google-crawlers.

[SEO]

We see some of them here; for example, right now

Google (AdSense) (2), Google (6)

... But Google isn't available in China so without VPNs you can't use it and can't learn a lot about it. Look:

连接超时

www.google.com 的服务器响应时间过长。

    此站点暂时不可用或者太忙。请稍后再试。
    如果您无法载入任何页面，请检查您计算机的网络连接。
    如果您的计算机或网络受到防火墙或者代理服务器的保护，请确认 Firefox 已被授权访问网络。

 And I am sure that Google has all necessary types of crawlers. You don't need to worry about it if your SEO is normal.

[JessicaJohansson]

Ok, Got It, Thanks for replying the informative information.

[Gay]

Jessica's comments more and more look like copy-pasted and botish.