You want:
int rowNumber=...;
string value = driver.findElement(By.xpath("//div[@id='productOrderContainer']/table/tbody/tr[" + rowNumber +"]/div[id='something']")).getText();
In other words, locate <DIV>
with the id "something" contained within the rowNumber
th <TR>
of the <TABLE>
contained within the <DIV>
with the id "productOrderContainer", and then get its text value (which is what I believe you mean by "get me the value in <div id='something'>
"