Romans 8:26
And in the same way, the Holy Spirit helps [us in] our weakness; for we do not know what we ought to pray for [Note: Some translators understand this as "how to pray"]. But the Holy Spirit goes to God on our behalf with groanings [in our hearts] that are not expressed [in words].
Philippians 4:6-7
Do not worry about anything, but in everything, by prayer and [special] petition, along with thanksgivings, you should make your requests known to God.
Hebrews 5:7
During His life on earth Jesus offered up prayers and special requests with loud crying and tears to God, who was able to save Him from dying, and He was heard because of His [earnest] devotion [to God].