your "master" examples work part of the time because of the WordDelimiterField can tell at indextime that the capital M in the middle of the word is a good place to split on.
without hints like that at index time, the only way to do "middle of the word" searches is with wildcard type queries -- which ar really inefficent. You might want to read a it about N-Grams and consider using an NGramTokenizer to chunk up your input words into ngrams for easy searching on pieces of words. : My index data is : : srinivasan,sweetheart,thomasmaster,thomasMaster.(totally 4 words) : Search data : vasan : Like that, if i search for "hear", its return nothing. The result should : Search data : Master or master : But mainly, i am unable to search a middle term in a word. I have -Hoss