Enhance search function in Android app

I have an Android app that contains many html files. Each file corresponds to a court rule. The files are named for court rules, and the text in each file begins with the court rule. For example, the text within a file named [login to view URL] would begin with "3. Filing Fees." I want to enhance the search function for this app in two ways: 1. The search results are ordered by number, low to high. The search function correctly orders rule numbers that are numeric - for example, if the search term is present in rules 4, 5, 5.1 and 5.2, search results display in that order. However, some rules are lettered as well as numbered - for example, rule 4a. The search function freezes when sets of rules include rules with both numbers and letters in their names. I would like the search function to be able to search rules that include letters as well as rules that include only numbers. Also, search results should be displayed in alphanumeric order. For example, if a search term is present in rules 4, 4a, 5, 5.1 and 5.2, the search results would display in that order. 2. When you touch an entry on the search results page, you are taken to the html page for that rule. I would like search terms to be highlighted in search results on the html pages. Please let me know if you have any questions.