RS, your post is unclear, at first it apeared you were working in a report, but now we can see its a dataport the initial post looked like you were filtering on vendor.:no." now it apears its a custom field.
Stop take a deep breath rethink and start again, write down the business need, don’t worry about code just explain what you want to achieve. If you can’t put this in clear business terms, then work with a senior to show you how to do this.