It is the young man ____ looked for ____ caught the murderer

I ______ it everywhere, but I didn’t _____ it. A．looked for, looked for B．looked for, find C．found, looked for D．find, look for

looked for和find与find out以及found和look for都有什么区别?
详细说明都分别用在什么地方!（最好举个例子）
明天月考,老师说这是重点!

初三英语选词填空
see,looked for,hunt ,dog ,kill ,wolf ,die,tear ,remind ,back ,hunt ,his,remember
More than seven hundred years ago,the Prince of Wales had a very big and brave dog called Gelert.
One day the Prince wanted to go 1.________ with his men.He told his 2.________ to stay at home and look after his baby son.The baby was in a wooden cradle (摇篮),which was like a small bed.
When the Prince came back from hunting,Gelert ran out to meet his master.He wagged his tail and jumped up to put his paws （前爪）on the Prince's chest.Then the Prince saw the blood on Gelert's jaws and head.
"What have you done?" the Prince said.He rushed into his house and 3.________his baby son.The cradle was lying on its side on the floor.The clothes were torn and there was blood on them.
"So you have killed my son?" the Prince said angrily."You unfaithful dog!" He took out his sword（剑） and 4.________ the dog.Just as Gelert was 5.________ ,he managed to bark.Then the Prince heard a baby call to the dog.
The Prince ran out of the house and saw his son lying on the ground unhurt.Near him was a dead 6.________.Then the Prince knew that Gelert had defended（保卫） the baby and killed the wolf.
The Prince ran 7.________ into the house but he was too late.Gelert was dead.The Prince was very sad indeed.8.________ ran down his face when he realized 'he had killed 9.________faithful friend.The Prince carried the body of his brave dog to the top of a mountain and buried him there.After this,the Prince never smiled again.Every morning at dawn,he walked up the mountain and stood by the dog's grave for a few minutes.
If you go to Mount Snowdon in Wales,people will show you where Gelert is buried.There is a sign by his grave.It 10.________people of a brave and faithful dog