awk search an output string between two strings

I would like to search for strings stored in searchstringfile.txt in inputfiles.

searchstringfile.txt

J./F.
Gls. Wal
F.
Tower

input1.txt

What is needed is J./F. 12 var Gls. Wal 16 interp. Tower 12 

input2.txt

Awk shall search for F. 16 pt. J./F. 22 

output.txt

input1.txt J./F. = 12 var
input1.txt Gls. Wal = 16 interp. 
input1.txt Tower = 12
input2.txt F.  = 16 pt. 
input2.txt J./F. = 22

This is the most i came up with:

awk 'NR==FNR { A[$0]; }{for(N=1; N<=NF; N++) if(A[$N]) print( FILENAME,  $N " = " $(N+1)); }' searchstringfile.txt input*.txt

awk 'NR==FNR{a[$0]=$0;next}{for(i=1;i<=NF;i++){t=m FS $i;m=$i;s(m,a);s(t,a)}}function s(x,b){if(x in b){print FILENAME,x,"=",$(i+1),$(i+2);i=i+2}}' searchstringfile.txt input*.txt
input1.txt J./F. = 12 var
input1.txt Gls. Wal = 16 interp.
input1.txt Tower = 12
input2.txt F. = 16 pt.
input2.txt J./F. = 22

The code produces always the first two instances after the searchstring and it shall not return the second instance of a searchstring.
Simply it shall only return the strings between two searchstrings.

Strings in which to be searched:

input1.txt: What is needed is J./F. 12 var II Gls. Wal 16 Tower 11 interp. 
input2.txt: Awk shall search for F. 16 J./F. 22 pt.  

Ouput:

input1.txt J./F. = 12 var II 
input1.txt Gls. Wal = 16 
input1.txt Tower = 11 interp. 
input2.txt F. = 16 
input2.txt J./F. = 22 pt.  

You may try something like this:

awk 'NR == FNR { r = r ? r "|" $0 : $0; next }
{
  s = $0; c = 0; split(x, rs); split(x, rl)
  while (match(s, r) > 1) {
    rs[++c] = RSTART; rl[c] = RLENGTH
    s = substr(s, RSTART + RLENGTH)
    }
  for (i = 0; ++i <= c;) {
    printf "%s: %s = %s\n", FILENAME, substr($0, rs, rl), \
      (rs[i + 1] - 2 > 0 ? substr($0, rs + rl, rs[i + 1] - 2) : \
        substr($0, rs + rl)) 
    $0 = substr($0, rs + rl)
    }
  }' searchstringfile.txt input1.txt input2.txt

With GNU awk 4 it's easier:

awk 'NR == FNR { r = r ? r "|" $0 : $0; next }
{
  n = patsplit($0, cr, r, s)
  for (i = 0; ++i <= n;)
    printf "%s: %s = %s\n", FILENAME, cr, s 
 }' searchstringfile.txt input1.txt input2.txt