yashwanth.258 said:
"Source of funds" ? Do we need to submit any other documents apart from Bank statements
You need to submit Bank certificate which mentions the account number, date of account opening, account holder names, current balance and average balance for last 6 months.
"Source of funds" refers to the means through which you obtained the mentioned amount - salary, savings, gift from parents/siblings, sale of property, etc.
If you obtained this money as a gift from someone, then you need to obtain a gift deed signed from that person stating that this money is a gift to you and need not be returned back.