I have 4 tables:

```
bag_of_words(
    ch_id,
    frequency,
    number,w_id
)

clinical_history(
    ch_complete,
    ch_id,p_id
)

patients(
    p_id,
    p_name
)

words(
    w_id,
    w_word
)

```

and I have a list of selected words. I need to select from tables `w_word`, `p_name`, `number`, `freqency`, and `ch_id`.

I have this query, but it is slow and I need it to be faster

```
SELECT  
    w_word, 
    p_name, 
    number, 
    frequency, 
    bag_of_words.ch_id
FROM
    bag_of_words
LEFT JOIN 
    words 
ON 
    words.w_id=bag_of_words.w_id
LEFT JOIN 
    clinical_history 
ON 
    bag_of_words.ch_id=clinical_history.ch_id
LEFT JOIN 
    patients 
ON 
    patients.p_id=clinical_history.p_id
WHERE 
    words.w_word IN (',,,,,')

```