I found a patent, and its similar patent begins with wo. How can we see whether we have entered the national stage of China?
EP is the European agency, and WO is the World Intellectual Property Organization. China is also a member of PCT. You must check whether you have applied in China.
US Trademark Office: http://www.uspto.gov/, European Bureau: http://www.epo.org/. Searching for patents internally.
The family description above does not have the country number of CN, so it should be that there is no application in China.