Searching a BYTE field

[MSNEWS]

I'm using the code below to read a file, I need to scan thru the file and
look for a specific word. The files will be in various formats, word, rtf,
pdf etc so the file will have binary characters.

I've tried converting the byte to a string with thestring =
System.Text.Encoding.Default.GetString(MyData) but that doesn't work, the
binary characters screw the conversion up

So how can I search a Byte field looking for a specific word?
Thanks
fs = New FileStream(filename, FileMode.OpenOrCreate, FileAccess.Read)

Dim MyData(fs.Length) As Byte

fs.Read(MyData, 0, fs.Length)

fs.Close()