Article fail to pick some content

[guojiangwei2]

html_content = """<P>&nbsp;&nbsp;&nbsp;&nbsp;最近一个月内，三圣股份共计登上龙虎榜1次，表明三圣股份股性一般。 (<A href='http://stock.jrj.com.cn/share,002742,lhb.shtml' target=_blank>更多龙虎榜查询请点击</A>)</P><P>&nbsp;&nbsp;&nbsp;&nbsp;公司主要从事    建材化工、医药。</P>"""
article = Article(html_content)
print(article.main_text)  # pick nothing

from lxml import etree
html = etree.HTML(html_content)
html.xpath('//text()')   # pick target content successfully

[guojiangwei2]

html_content = """<p>hello, word hello, word hello, word hello, word hello, word hello, word</p><p>hello, beijing. hello, word hello, word hello, word hello, word hello, word</p>"""
html_content2 = """<p>hello, word.</p><p>hello, jiangwei.</p>"""

Article(html_content).main_text  # correctly parse target content
Article(html_content2).main_text  # pick nothing