Rules for Phrasal Verbs!?

Do you think there're some rules for Phrasal verbs?
I still belive there're. Because I think if there were no rule, English would not be a language!(Sorry but my English is very bad!)
Are there rules of their meaning: think over, take over, look over, leave over...etc(each one has "over")
I know what I type is full of grammar mistakes, so please show them to me!
THANK YOU VERY MUCH!

I don't think there are any rules because they are normally irregular. Some of your examples can be simplified by looking at the first verbs to give you an idea of their meanings. However, the whole often has a different meaning to the individual parts. e.g. look over means more than just looking; it can mean to supervise: "Look over the children" or to verify: "Look over these accounting figures".

So you're best off learning them as is, like you would complete phrases and simple verbs.