'Look for' and 'find' are very similar - " to go and search for something". But when you use 'find', you are implying a lot more that you are going to use the result of that search in some way.
Example: When you are in a shop and say "Look for some apples", you are saying "go and search for some apples". There's no strong suggestion what to do after the apples are found unless it is already implied in the context of the conversation. But if you say "Go find some apples", you are saying "go search for some apples" and implying that once these apples are found something will be done. Apples brought back, whatever.