In a drawer of his office desk are many scripts of questions collected during lectures. For example, many of them asked how could one handle a broken relationship with a lover and failure in job hunting.

Lu had also been a student counselor for eight years at the university based in Wuhu, Anhui province. He once launched an activity called "Say Your Expectations to the Counselor" and he read them very carefully.

One of the messages left by student Cao Keliang said nothing but "leave me alone", which attracted Lu's attention. Lu later learned that the student was from an impoverished family and often skipped classes to play cards with schoolmates.

He was not bothered by the message but tried hard to help, including gaining financial support from the university for Cao.

Finally, the teacher and student became good friends. As Cao said he wanted to take part in the postgraduate entrance exams, Lu encouraged him and gave him guidance.

Cao later realized his dream and became a teacher at China Jiliang University based in Hangzhou, Zhejiang province.

Lu's extracurricular lectures have attracted more than 100,000 attendees so far, and his articles shared on Weibo, China's microblogging platform, have been read more than 20 million times.

"The professor always uses unique methods to make abstract knowledge intuitive," said Lei Jiwen, a senior student.

Instead of the stereotypical narration for such abstract topics, Lu's class wins the hearts of students with innovative presentations and fascinating storytelling.

He prefers tailoring the lectures for attendees of various major backgrounds.

For example, for students majoring in music, he would start from the stories of the German musician Beethoven and Chinese musician Nie Er, who composed the music for the Chinese national anthem.

Last year, he tried to explain the centennial history of the CPC, so he conducted the lectures with several models of boats and ships.

The models included the Red Boat, where the founders convened the first CPC National Congress and announced the Party's founding in 1921; the boats that carried the Red Army during the Long March; and the PLA Navy's modern CNS Liaoning aircraft carrier.

Some of the lectures were even conducted in the form of walking tours. In one of the tours in 2013, he brought several students to travel on foot for more than 200 kilometers to Anhui cities along the Yangtze River.

"Simply preaching on a podium can often fail to solve problems, while only by becoming friends with the students can we teachers give them warm accompaniment in their life," said Lu.