It isn't just a search engine; there is an entire for-China-by-Chinese ecosystem [1]. To answer your direct question, yes, every Google online property is inaccessible within the PRC to non-registered commercial entities, and has been for the past 7 years. If you are a appropriately-registered commercial entity that can afford it, my understanding is dedicated lines (assumed monitored by the PRC) may be purchased with access to the outside world.

[1] http://www.mandarinzone.com/top-10-popular-chinese-websites/

Edit: my apologies, bad wording. Kudos to xiaoma for catching my mistake, thank you 小马 (my guess at your name in 中文）。Today, all Google properties I'm aware of are blocked. The blocking was implemented gradually across Google properties over the past 7 years. The search engine has been blocked for the past 7 years, since the beginning of the block.