Recommendations

Both movies deal with fairy tale stories with a horror genre spin on them.

Three... Extremes is the sequel to Three. Both movies deal with 3 different stories from 3 different directors from 3 different counties. Get why it's called Three?

Both involve the relationship between a career woman and a high school student. High School King of Savvy is more lighthearted than I Hear Your Voice.

Similar family style drama with funny and cute moments, in my opinion the acting is much better in Smile, You

Both dramas are about divorced couples which meet again after some years

Both are amazing medical dramas that challenge the hierarchy in place.

Both are amazing medical dramas that challenge the hierarchy in place.

Can't watch Ring Virus without watching the very first film in the series

Both are hilarious, with zany characters and over-the-top acting. Somewhat more oddball than typical Korean comedy dramas.

Same scriptwriter (she has typical own "handwriting") and you will find Sung Joon in both shows. DoR can be INR4.

Same scriptwriter. You can find, that there is same main actress in both dramas.

There is same scriptwriter, so you should expect same atmosphere.

the two female main stars (wei mandy and lee vivi) in I do are also in Love,Now

Both feature Karina and Tanaka Kei as the leads and feature many similarities in plot and themes.

Both dramas are very sad love stories set in the qing dynasty.
In both the female leads start as innocent girls and are forced to change due to the circumstances.
Both dramas revolve about palace intrigues of power, love, sacrifice and the life of the women.
Yongzheng Emperor also appears in both, in "Legend of Concubine Zhen Huan" as the ruler and in "Desperate Love" as a child.