"Seek", "search" and "look for" are not 100% interchangeable.  For some sentences, all three verbs could be used.  For other sentences, only one or two of the verbs will be appropriate.

Seek.  I would not use "seek" to describe the action of looking for ordinary objects or people (when the object/person is known to you but you just don't know where to find them at this moment).  It will sound strange if you say, "I am seeking my car keys.  Have you seen them?"  I would not say, "I am seeking Aziz Omar at the airport."  ("Search" and "look for" can be used :  "I am looking for my car keys." "I am searching for my car keys."  "I am searching the house to find my car keys.")

Seek.  Seek can mean to try to find things or to discover things...but they are often things that are intangible or that we aren't sure (yet) if they exist.  "He seemed to be seeking a purpose in life."   "The family is leaving their country and seeking a safer place to live."    Seek can also mean to try to obtain.  "He went to his professor to seek some advice about the research project."  "After someone is robbed, they should seek help from the police."

Search.  "To search for" something can mean "to look for" something but "to search" (without the word "for") can mean "to carefully examine a location while trying to find something."  For example, "I am going to search my car to see if I left my water bottle there."  "I've searched the entire airport and I didn't find Aziz Omar anywhere."   "The police officer searched Jack to see if he was carrying any drugs or weapons."

I could write quite a few more paragraphs about these three verbs.   But I think this is enough for now.  Please ask me if you still have any questions.  Or, if you have a specific sentence and you would like to know which of these three verbs will be best for that sentence, please feel free to ask me.

Can a native speaker help me?

They mean almost the same but has subtle nuance: 

To seek means to go and look for and try to find(physically and/or by questioning) something or someone - there has to be some movement by the subject : "I am seeking Jack at the airport." = I am at (or will go to) the airport and I am trying to find Jack.

To search means to look for something; it can be done without movement, "I am searching Jack at the airport." = I am at the airport and I am checking Jack's body and possessions."

Another fundamental difference is that the object of seek is item while the object of search is place.

So there is a subtle difference when you utter: I am seeking Jack/looking for Jack/searching Jack.