Without seeing any code, all I can guess is that you're putting the data into an HTML tag attribute without quoting it, e.g.:
echo "<input type='text' name='example' value=".$row['value'].">";
If there is a space in $row['value'], then the resulting HTML would be:
<input type='text' name='example' value=more than one word>
In that case, the value would be set to "more" and "than one word" would be ignored as invalid attributes. You should do something like:
echo "<input type='text' name='example' value='".htmlentities($row['value'], ENT_QUOTES)."'>";
