"Delight yourself in the LORD; And He will give you the desires of your heart." Psalm 37:4
The original Hebrew for the word 'Delight' literally means 'to be pliable or malleable'. While there are other choices, including the word "delight" given in most translations, the key for using 'malleable' here comes in verse 5:
"Commit your way to the LORD, Trust also in Him, and He will do it."
If we allow 'our way' to become God's way, by allowing Him to mold us, by being 'malleable', and trusting in Him, He will give us the desires of our heart.
The Hebrew word for 'desires' here is actually "petitions", or requests. We petition the Lord in prayer. So, if we allow ourselves to be molded into what God wants us to be, we will have greater success in having our prayers answered in the affirmative.
All of God's blessings are conditional, even salvation, the condition of which is repenting of sin and accepting Christ as Lord and savior. Here, the condition to having more prayers answered positively is allowing God to mold us and use us according to His will and purpose, not ours.
Be malleable, blessed!