By design SilkTest reads and writes values to files (such as .txt or .csv) in a sequential manner; therefore if you wish to retrieve the contents from a specific row you should implement the code below. This code reads each line of a text file before returning the contents of the specific row that you are interested in. In the example below we are looking for the contents of the 10th line in the text file.
 

[-] testcase ReadFromFile() appstate none
 [ ]
 [ ] HFILE hFile1
 [ ] STRING sValue
 [ ] INT iCount = 0
 [ ]
 [ ] hFile1 = FileOpen ("C:\ReadList.txt", FM_READ) // Open the file
 [ ]
 [-] while(FileReadLine (hFile1,sValue ))
  [ ] iCount ++
  [-] if (iCount ==10)
   [ ] print(sValue)
  [ ]
 [ ] FileClose (hFile1) // Close the file
 

In the above example the while loop reads the contents for each line/row of the text file; then after each iteration it increments the counter value by 1.  The If statement is then used to return and print the contents if the row count is equal to 10.