Si claro Puedes filtrar la consulta o aplicar ese condicional al tr on a los td
Código PHP:
Ver originalif($var1!=0 && $var2!=0 && $var3!=0 && $var4!=0){
echo "<tr>
<td><center>$var1</center><input name='txtnopro[]' type='hidden' value='$var1' size='48'readonly/></td>
<td><center>$var2</center><input name='txtcotiz' type='hidden' value='$var2' size='5' readonly/>
<td><center><input name='txtcantidad[]' type='text' value='$var2' size='1'/></center></td>
<td><center>$var4</center><input name='txtcotizado' type='hidden' value='$var4' size='5' readonly/>
<td><center>$var3</center></td>
<td><textarea name='txtobs[]' type='text' value='' size='15'></textarea></td>
</tr>";
}