Cancellation of sale of agreement from buyer side

I made an agreement with the plot owner. I paid 50,000 rupees. I want to cancel the agreement, because the area wouldn't get developed more than 10 years even. I want to build a house for my mother and for my family. I want to cancel the agreement. I am from Telangana state. I made an agreement on Rs.100 stamp paper. the description is like this on agreement. I paid only Rs.50000 to seller. And wrote backside of the agreement with witness signatures. I want my money back and cancel the agreement. How will I get my money back. Please suggest, my mother worked for Rs.15000 monthly salary. NOW THIS AGREEMENT OF SALE WITNESSES AS UNDER I.That the Vendor hereby agreed and promise to sell the schedule mentioned Property to the Purchaser for a sale consideration of Rs.4500/-(Rs.Four thousands Five hundred only)/-Per Sq.yds,total amount of the said land is Rs.8,05,500/-(KS. Eight Lakhs Five thousands Five hundred only)/- 2.That the Vendor has received an amount of Rs.1,00,000/-(Rs.One lakhonly)/-paid on [deleted] and the Remaining balance amount will be paid at thetime of Registration within One and half month,and the vendor will register the said property in the name of purchaser or whom so ever the purchaser desires.Thatthe Vendor is responsible for any disputes on the said property. 3.That the Vendor shall obtain necessary clearance Certificate/Ownershipcertificate or permissions from appropriate authorities,which are essential for thepurpose of execute for sale deed register in the name of the Purchaser. 4.That the Purchaser shall bear the expenses towards stamp duty andregistration charges. 5.That the Vendor hereby assure and make believable the Purchaser thatthe schedule mentioned property is free from all sorts of charges,liens,interests,Encumbrances,attachments,disputes and no dues are out standingagainst the schedule mentioned property and for all such Liabilities,theVendors shall be liable. 6.That the Vendor hereby further assure and make believable thePurchaser that he got perfect right,clear and alienable title over the scheduledmentioned property and no other person or persons have got any manner ofright or title therein.That vendor will give all the necessary originaldocuments to the purchaser for the purpose registration.