I don't know if by dahi poori you are referring to the concoction that also goes by the name Papdi ka chaat : crisp flour wafers, w/, w/o garbanzo beans, thich beaten yoghurt, tamarind sauce?
While the papdi-s in question do have carom seeds etc. incorporated in their dough and have a short crust and may be slightly thicker etc.,a serviceable homemade 'fix' [quicker, cheaper!] may be made from good quality wheat flour tortillas, cut up and deep fried. [Perhaps you could also try brushing these with oil and baking them to crispness, having placed them on wire racks; I have not.]
You have canned chickpeas (drained), tamarind and green chutneys pre-made plus MDH brand chunky chaat masala on many supermarket shelves these days. Chopped red onions, and thick creamy yoghurt (beaten), Greek style, of fat level from 0-12 % appropriate for your diet and lifestyle: adjust seasonings with a bit of lime juice and green/red fresh Thai chillies, salt, if need be, and you are in business!
You may even wish to sprinkle the finished plate with SEV, the thin strings of fried chickpea flour (found packaged in Indian groceries or through mail order), or with BOONDI-s, tiny round balls of same, for added crunch. This is not necessary, and may be heterodox, for this chaat! Similarly non-traditional but lovely: sprinkle a few fresh pomegranate vesicles over, for a special visual and taste treat.
Haha sorry about my lack of knowledge in Indian cuisine!
But yes, your description of the Papdi ka chaat sounds about right to what I had-definately with the crispy wafers.
I took a picture of it too...here we go (is this it?):
What's the name for this one?
And thank you for your extensive knowledge on my beloved Papdi ka chaat