My ultimate favorite tool is an exhaustive concordance. If I can remember a word from a verse, I can look it up. Or if I want to see all the verses that include a certain word, I can look them up. The term "exhaustive" does not mean it's exhausting just to pick it up, although with such a huge book one could easily draw that conclusion! Rather, it means that even every iteration of the word, "the," is included. Sort of the equivalent of saying a book is "unabridged."
Because so much of my Bible memory has been done in NIV, I own the Zondervan NIV Bible Concordance. However, I also have a Strong's Exhaustive Concordance of the Bible for KJV, and I will tell you why in two words: Word Study.
First published in 1890 when King James was about the only English version available, James Strong's concordance catalogues and numbers every single Greek and Hebrew word in the original text. Every word in the English portion of the concordance is keyed to its actual original-language equivalent. This provides additional clarity for study, because sometimes several slightly different words all were interpreted into a single English word. Sometimes this just represents a choice of the author; sometimes it provides additional illumination.
For example, the Old Testament word for "help" comes from various Hebrew words. Consider all these different words that translate as "help," and the nuance of their meaning:
"If you see the donkey of someone who hates you fallen down under its load, do not leave it there; be sure you help him with it." Exodus 23:5
5800 asab: to loosen, i.e. relinquish, permit, etc. As in, to commit self, to fortify, help, leave, refuse.
"If you see your brother's donkey or his ox fallen on the road, do not ignore it. Help him get it to its feet." Deuteronomy 22:4
6965 quwm: abide, accomplish, be clearer, confirm, help, hold, lift up
"'Curse Meroz,' said the angel of the LORD. 'Curse its people bitterly, because they did not come to help the LORD, to help the LORD against the mighty.'" Judges 5:23
5833 ezrah: feminine form of 5826--to aid
"And they said unto the messengers that came, Thus shall ye say unto the men of Jabeshgilead, Tomorrow, by [that time] the sun be hot, ye shall have help. And the messengers came and shewed [it] to the men of Jabesh; and they were glad."1 Samuel 11:9 KJV
8668 teshuah: rescue(in the sense of 3467). Deliverance, help, safety, salvation, victory
"And he said, If the Syrians be too strong for me, then thou shalt help me: but if the children of Ammon be too strong for thee, then I will come and help thee." 2 Samuel 10:11
3447 yashat: to extend, hold out.
"The king replied, 'If the LORD does not help you, where can I get help for you? From the threshing floor? From the winepress?'"2 Kings 6:27 NIV
3467 yasha: to be open, wide or free, i.e. to be safe
"Day after day men came to help David, until he had a great army, like the army of God." 1 Chronicles 12:22
5826 azar: to surround, i.e. protect or aid.
After getting an idea of the different ways "help" is used in the Old Testament, if I wanted to study it a little more deeply, I would then look it up in my Vine's Expository Dictionary of the Bible. When I do that, I discover that the most frequent usage of help is the 5826 sense found in 1 Chronicles 12:22:
This word and its derivatives are common in both ancient and modern Hebrew. The verb occurs about 80 times in the biblical text. Azar is first found in the the Old Testament in Jacob's deathbed blessing of Joseph: ". . . The God of thy father, who shall help thee . . ." (Genesis 49:25).
Help or aid comes from a variety of sources: Thirty-two kings "helped" Ben-hadad (1 Kings 20:6); one city "helps" another. . . . Of course, the greatest source of help is God Himself; He is the "helper of the fatherless" (Psalm 10:14).
In the end, help still means help in all the above passages. But in my word study I have learned the glorious variety of ways to express one's need for help. As a wordsmith, I appreciate that! God probably knew he would be hearing that a lot, so he gave us lots of words to play with.
1 I lift up my eyes to the mountains—
where does my help come from?
2 My help comes from the LORD,
the Maker of heaven and earth.