Hello all,
Please tell me What is Keyword Proximity. and how to use in SEO.
Hello Anshulseo, you should search google once before posting a thread here 
I just searched Keyword Proximity and got the result on top.
You should check it out here: http://keyword-proximity.com/what-is-keyword-proximity-and-what-can-it-mean-for-you
In a simple word, keyword proximity is the location of the keyword. Generally, people put it on the start of a sentence.
Keyword proximity is an outstanding combination of keywords and density. Therefore, the focus on the keywords in a sentence near the location and frequency of its words are used, also taking into account the distance between them.
The distance between two keyword is called Keyword Proximity
From a marketing perspective: how close to the beginning of your TITLE, and the beginning of your page content. Your target keywords should be in the first sentence or paragraph, and also in the page title, or product description.
Keyword proximity measures the nearness between two search phrases. In general, the closer the search phrases are, the better.
For Search Engine Optimization, the proximity of the keywords or keywords included in a phrase in regards to each other and one another is a vast amount of is the basis of using the appropriate combination of the words in the titles on pages, headers, paragraphs and web page content.
Keyword proximity is the closeness between two or more keywords. Your keywords should be close to each other in content of web page.
For Example: This post is related to “Internet Marketing”. The word “Internet Marketing” is not a key word. It is a key phrase. Here “Internet” is a one keyword and “Marketing” is another keyword.