A product that supports Indian languages usually means one that displays them. Searching and sorting them is a different problem, and it is where the support turns out to be superficial. The assumptions baked into most databases and search libraries — that sorting is byte order, that a word is a sequence of letters separated by spaces, that users type in the script the content is stored in — hold poorly for Indic text.
Sorting is the first surprise. Byte order in Unicode does not produce the order a Hindi or Tamil reader expects, because Indic scripts combine consonants with vowel signs and conjuncts in ways that a naive comparison gets wrong. What you need is a collation appropriate to the language, and it is language-specific rather than script-specific — the same characters sort differently by convention in different languages. Most databases support locale-aware collation; the work is choosing it deliberately rather than accepting the default.
Then normalisation, which causes bugs that look impossible. The same visible text can be encoded in more than one sequence of code points, so two strings that appear identical do not compare equal, a search fails, and a duplicate record gets created. Normalising all text to a single Unicode form on write is a one-line decision that prevents an entire category of defect, and retrofitting it means reprocessing everything you already stored.
The largest practical issue is that Indian users do not reliably type in the script they are reading. A user looking for a Hindi product name will frequently type it in Latin letters, phonetically, and spell it in one of several defensible ways. Search that only matches the stored script returns nothing and the user concludes the product does not exist. Handling this means transliteration — indexing a Latin representation alongside the native script — plus fuzzy matching, because there is no single correct romanisation of most Indian words.
Names deserve their own attention because they are what people search for most. The same person's name may be stored in one script and searched in another, may have several accepted spellings in Latin, and may include initials that expand differently. A search that requires exact matching will fail routinely on entirely legitimate input. Indexing multiple representations of a name, and matching loosely with ranking rather than strictly, is what makes a directory or customer lookup usable.
The cheap test that reveals all of this takes an afternoon. Put fifty real records with Indian-language content into a copy of your system, then search for each one the way a user actually would — in the native script, in phonetic Latin, with a plausible misspelling, and with only part of the word. Count how many you find. Teams that run this exercise are consistently surprised, and the fixes it points to are usually configuration and indexing rather than anything architectural.