Yajra\Datatables\Request::isSearchable PHP Method

    public function isSearchable()
    {
        return $this->input('search.value') != '';
    }

 /**
  * Perform necessary filters.
  *
  * @return void
  */
 public function filterRecords()
 {
     if ($this->autoFilter && $this->request->isSearchable()) {
         $this->filtering();
     }
     if (is_callable($this->filterCallback)) {
         call_user_func($this->filterCallback, $this->filterCallbackParameters);
     }
     $this->columnSearch();
     $this->filteredRecords = $this->isFilterApplied ? $this->count() : $this->totalRecords;
 }