I want to make it more clear.
I wanna see y label clearly
For this problem you need to use subplots.adjust and ylabels fontsize
Make more rows for subplot.
Check the modified code below
import numpy as np
import matplotlib.pylab as plt
import seaborn as sb
data = sb.load_dataset("tips")
num_col = data.select_dtypes(include=[np.number]).columns.tolist()
rows = 2
if((((len(num_col) + 1)/rows)%rows) ==0): #when num of cols are divisable by rows
cols = (len(num_col)+1)/rows
else:
cols = ((len(num_col)+1)/rows) + ((len(num_col)/rows)%rows)
fig, axs = plt.subplots(rows,cols, figsize=(10,10))
fig.subplots_adjust(hspace = 0.1, wspace=0.5)
axs = axs.ravel()
for j,k in enumerate(num_col):
b = sb.boxplot(y = k, data=data,ax = axs[j],)
b.set_ylabel(k,fontsize=20)
gives

P.S. : It is always a good practice to give a small sample of your data and full code with imports to make it reproducible.