If you search for "New York" rather than "New York Street" or "New York Avenue", all results that have "New York" in their address will be displayed in the results. However, if you search for "New York Avenue", only the addresses that were entered into the MLS with a street address of "New York Avenue" will be returned. Some of your possible results will be missing because some items are entered into the MLS with abbreviations like "New York Ave'. This is true for subdivision names, towns, etc.
If you already know the MLS # of your desired property, only enter the 5 digit number. For example, enter "71324" and not "R71324A" that some websites display.