Knuth-Morris-Pratt is an Algorithm for searching a text for a string. It's a very commonly used algorithm and is very fast. TODO: write about how it works. Here is a Delphi implementation of the kmp search algorithm. Use those two functions like this: var str_to_search_for: string; str_to_search_in: string; begin str_to_search_for := 'Word(s)'; str_to_search_in := 'String in which you will search for the word(s)'; kmp_search_next( str_to_search_for, str_to_search_in, kmp_table( str_to_search_for ) ); end;