(VB6) richtextbox loop for read data help..

i have some data in richtextbox like this..

00001 abcd 0001 efgh
00002 jklm 0002 nopq
00003 rstu 0003 vwxy
.............................
etc,

and i want it to produce it in this format..

abcd efgh
jklm nopq
rstu vwxy
.............
etc,

to get that i used this
mid(richtextbox.text, 7, 4) & mid(richtextbox.text, 17, 4)

but it only show the first line..
i dont know how to loop the function and the next line will show up too..
please help me.. i'm beginner for using VB6.
*sorry for my english