Use specified quantifier in grep to retrieve satisfied vocabulary I try to grab words from a file:

$ grep -o '\*\*[^*]*\*\*' Principles_20_LifePrinciples.md | grep -v -e "Origin" -e "Etymology"
**circumstance**
**case**
**condition**
**Anxiety**
**anxiety**
**the state of feeling nervous or worried that sth bad is going to happen**
**a worry or fear about sth**
**a strong feeling of wanting to do sth or of wanting sth to happen**


The result I intend is to get only words:

**circumstance**
**case**
**condition**
**Anxiety**
**anxiety**


Refactored code with specified quantifier {,20}:

$ grep -E -o '\*\*[^*]{,20}\*\*' Principles_20_LifePrinciples.md


Unfortunately, it returns nothing.

How to solve such a problem?
Without seeing the full text of the file, wouldn't:

grep -o '\*\*[a-zA-Z]*\*\*' file


work?