t may be because this is a relatively specific research question, and there may not be many studies that have examined this particular relationship.
However, there are some studies that have explored related topics and may provide some insights into the relationship between approval seeking motivation and emotional intelligence among students. For example, some studies have looked at the relationship between emotional intelligence and motivation more broadly, or have examined the relationship between specific types of motivation (such as achievement motivation) and emotional intelligence.
Here are some potential sources that may be helpful in your search:
"Emotional intelligence, motivation, and academic performance among college students" (Kafetsios & Zampetakis, 2008)
"Emotional intelligence, academic motivation, and academic achievement in high school students" (Rahimi et al., 2013)
"Achievement motivation, emotional intelligence, and academic performance among college students" (Mahyuddin et al., 2014)
"Motivation and emotion regulation in college students: A study of the relationship between achievement motivation, emotional intelligence, and emotional regulation" (Hershberger et al., 2016)
While these studies may not directly address approval seeking motivation specifically, they may provide some insights into the relationship between motivation and emotional intelligence among students more broadly.
You may also want to try using different search terms or searching in different databases to see if you can find more relevant studies. It may also be helpful to consult with a research librarian or academic advisor for further assistance.
In 2007 I conducted an experiment with students at the Institute of Philology in Kiev. There is a small article in Russian with the results of that experiment. It seems to me to be on your subject.
I do research in the field of socionics, it's one of the branches of Jungian typology.
Article Опыт лингвосоционического ассоциативного эксперимента