Recommendations

They are under the same genres: romance, school, youth, friendship, slice of life.
I feel like My youth has a similar setting to River flows to you. This focuses on friendship. The boy is always there for the girl no matter what. There are rivals too ;)
RFTY shows a boy and a girl who grew up together and one eventually falls in love with the other, which is quite similar to my youth .

Differences

River flows to you has more family involvement

The girl is very poor in RFTY

Few friends

both psychological dramas and tells the story of people going through trials
both are very dark, good stories

Main lead find out disease in sec without any test by analyzing symptoms
main lead has failed past
main lead confident about their treatment theory on patients that'swhy they don't listen anyone only follow their instincts

Main lead find out disease in sec without any test by analyzing symptoms
main lead has failed past
main lead confident about their treatment theory on patients that'swhy they don't listen anyone only follow their instincts

Main lead find out disease in sec without any test by analyzing symptoms
main lead has failed past
main lead confident about their treatment theory on patients that'swhy they don't listen anyone only follow their instincts

Main lead find out disease in sec without any test by analyzing symptoms
main lead has failed past
main lead confident about their treatment theory on patients that'swhy they don't listen anyone only follow their instincts

Main lead find out disease in sec without any test by analyzing symptoms
main lead has failed past
main lead confident about their treatment theory on patients that'swhy they don't listen anyone only follow their instincts

both male lead treats his patients with full devotion and without discrimination. However, his medical license gets suspended as a result of a medical malpractice incident . so how he will be come back its interesting to watch

Both male lead are god from sea/water in human realms their trusted servant live from generations both male lead comes human world to find out precious thing and encounter female lead for whom they fall in love as times goes both male lead found some how female lead life at stake on consequence of male lead mission

Note : "starry night starry sea" is better one

They are both best friends who fall in love with the same man at some point and become enemies because of that.

SIMILARITIES
-Both include supernatural elements
-Lee Seung Gi plays the male lead in both dramas
-Love between a human and a 'supernatural being'
-Both set in the past (a Korean odyssey shifts into the past quiet a few times whereas thats when Gu Family Book is set)


SIMILARITIES AGAIN BUT INCLUDE SPOILERS:
SPOILERS:
-Both tragedy at the end.


SERIOUSLY A HUGE SPOILER FOR BOTH DRAMAS:



-A main character dies at the end of both dramas.

Different stories but same feel. Similarities between the two are:

1) Smart and Witty FL
2) FL has a different love interest initially
3) ML falls in love first
4) Once the Lead couple get together they are loyal and trust each other
5) Both are slow paced drama
6) Amazing chemistry

If you like one, definitely give the other a try.

Both leads stumbles with a mysterious lady of many names/lives and esoteric space-time renown
Haunted by visions of ghosts
Employed, servant running errands at Hotel/store that grants wishes to costumers with a price
Visually stunning , stylish part realistic and fairy tale(Sageuk) themes
**watch the Anime**

- both female leads study English
-both quite light and fluffy dramas
-both males leads study physics
- both male leads are seen as mature

Complicated love with third party interference. However, one summer night is for more mature views since it’s too explicit.