Bootstrap code

Question

I have simple row code

<div class="row">
<div class="col-md-3">col md 3</div>
<div class="col-md-3">col md 3</div>
<div class="col-md-3">col md 3</div>
<div class="col-md-3">col md 3</div>
</div>
So it should be
col md3 col md3 col md3 col md3
But I have :
col md3 col md3 col md3
col md3
Why it happened ? How fix it ?

Answer 1

The code seems to work perfectly my friend........ :-)

Answer 2

I'm not user of Bootstrap, but it seems that its grid system require at least a main parent container (even with only one row) with class 'container' or 'container-fluid'... look at these two links to learn further:

https://www.w3schools.com/bootstrap/bootstrap_grid_system.asp
https://v4-alpha.getbootstrap.com/layout/grid/

Answer 3

No I want this
col md3 col md3 col md3