Hello txesmi,
Thanks to your input I could completely solve my problems

I have written a small Ascii to Unicode Converter Function,
I will post it for anyone who is interested

.
function ascii_to_unicode(STRING* ascii_string)
{
short t[30];
var current_ascii_value;
var i = 1;
for (i=1; i<=30; i++)
{
if (str_getchr(ascii_string, i) != 0)
{
t[i-1] = str_getchr(ascii_string, i);
}
}
return(str_createw(t));
}
To use this function accordingly, all I have to do is the following:
STRING* str = "";
var fhandle = file_open_read("file.txt");
STRING* unicode_string = ascii_to_unicode("test1");
file_find(fhandle,unicode_string);
file_seek (fhandle,-1,1);
file_str_readtow(fhandle,str,";",NULL);
file_close(fhandle);
EDITED:
This code still has a bug, scroll down