Doing a google search I was fortunate enough to find this answer from 2 years ago, on a question I had asked my self… 
Therefore a working loop can simply be done as:
idHits = Vector{Int64}()
ind = 0
while true
ind = Base._searchindex(TranscodedText, SearchNeedle, ind+1)
if ind == 0
break
end
push!(idHits,ind)
end
Kind regards