SOSL Query: Getting different number of records while searching with 1234* and abcd1234*

Question

I have a community page. It has a search box and a list view to display the search result. Below is the Query I'm building: (It will search in 15M total records)

List<List<sObject>> searchList = [FIND '1234*' IN ALL  FIELDS RETURNING Service_visit__c 
                                  (Account__r.Name, Account__r.Location__c, OId, Start_Date__c, Address1__c, City__c, State__c, Report_Type__c ORDER BY Start_Date__c DESC LIMIT 200 )
                               ];

Above SOSL is resulting in less record assuming 30 counts.

But When I'm searching with some other string 'abcd 1234*', It's resulting in many records (150 records):

List<List<sObject>> searchList = [FIND 'abcd1234*' IN ALL  FIELDS RETURNING Service_visit__c 
                                  (Account__r.Name, Account__r.Location__c, OId, Start_Date__c, Address1__c, City__c, State__c, Report_Type__c ORDER BY Start_Date__c DESC LIMIT 200 )
                               ];

Answer 1

Those are simply different queries that match different result sets.

SOSL does not perform substring matching (matches that start within a token). 1234* will match any token beginning with 1234, but it won't match, for example, abcd1234. Conversely, abcd1234* will match abcd123456, but it will not match 123456.

There are some examples demonstrating this principle in the FIND section of the SOQL and SOSL Reference:

Asterisks match zero or more characters at the middle or end of your search term. For example, a search for john* finds items that start with john, such as, john, johnson, or johnny. A search for mi* meyers finds items with mike meyers or michael meyers.

Emphasis mine. Note how the wildcards apply only in the middle or at the end of a token that is part of the search term.