This refers to Indian law allowing muslims to live under sharia for family matters.
The rule itself is referred to as "triple talaq" and is part of sharia. In Sunni islam, basically men can abandon women, without any (any) limit immediately and without consequences (they get to take possession of everything the woman owns as well). They can take the kids if they want, including kids that have been conceived but not born yet (technically they should take the kids, but that's not what happens in practice).
Women face progressively harsher physical punishments for abandoning a man. If they remarry without his permission, they face (extra cruel) execution (stoning, often with the kids and family forced to watch).
Edit: links
http://www.aljazeera.com/indepth/features/2017/05/tripple-ta...
The problem with wikipedia articles is that they try to bury the message in detail. Read it through 5 times and you'll slowly realize what the rule is:
https://en.wikipedia.org/wiki/Divorce_in_Islam#Talaq_al-bid....
TLDR: in mainstream Sunni islam what I said is true. Allowing women contractual divorce is a Shi'a practice, and not practiced by >85% of muslims worldwide (what is it ?Essentially a prenup allowing for divorce under stated circumstances, which cannot be initiated directly by the woman). Once you look up the numbers, you'll see that the worst kind (the pure triple talaq) is followed by some ~80% of muslims worldwide, and the contractual thing is an exception for Shi'a only (and is one of the main stated reasons of recent Sunni genocides against Shi'a in the middle east). You'll see that the text does in fact say the overwhelming majority follows the worst practice, but not on your first read.
These statements in wikipedia are true, but they're true like saying "your phone company cannot just terminate your service", which is true. And then give the entire contract and details on how this contract is affected by 5 different jurisdictions, which is of course the entire rule. But all it serves is to cloud the issue.
Of course, in all realistic circumstances, your phone company can in fact just tell you to fuck off without so much as giving a reason.