Siva S

Hi Irdiansyah,

Your Responsive Theme have a multiple option for grid size

You can find the css code in styles.css under you current theme folder

Currently you theme using three rows with class (col-300) , you can change the size of the row by changing the class name of any following

.col-60,
.col-140,
.col-220,
.col-300,
.col-380,
.col-460,
.col-540,
.col-620,
.col-700,
.col-780,
.col-860 {
  display: inline;
  margin-right: 2.127659574468%;
}

.col-60 {
  width: 6.382978723404%;
}

.col-140 {
  width: 14.893617021277%;
}

.col-220 {
  width: 23.404255319149%;
}

.col-300 {
  width: 31.914893617021%;
}

.col-380 {
  width: 40.425531914894%;
}

.col-460 {
  width: 48.936170212766%;
}

.col-540 {
  width: 57.446808510638%;
}

.col-620 {
  width: 65.957446808511%;
}

.col-700 {
  width: 74.468085106383%;
}

.col-780 {
  width: 82.978723404255%;
}

.col-860 {
  width: 91.489361702128%;
}

.col-940 {
  width: 100%;
}

I hope this could be helpfull to you

It may be because of your theme.
Try to find out the excerpts hard coded inside the template