private int getPreviewColumnIndex() {
		int previewColumnIndex = 0;
		for (int i = 0; i < this.getModel().getColumnCount(); i++) {
			if (this.getColumnName(i).equals(HEADER_COL_PREVIEW)) {
				previewColumnIndex = i;
				break;
			}
		}
		return previewColumnIndex;
	}
Gathers the search strings for each instruction and returns them as a
single string.

@return the complete search string
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/instructionsearch/ui/PreviewTable.java