You look at them directly from the phone. Verizon only shows time and inbound/outbound number of who sent the text online. Unless it's for a legal reason which requires their VSAT team to speak with an attorney, Verizon isn't going to let you read someone else's text. Their standard customer service doesn't have this ability to access text archives anyway.
How do I read the actual text messages on one of my lines
If Message+ is being used with Integrated Messaging, you can log in to Message+ (on desktop, laptop, tablet or another phone) using the lines' profile password and see/use text messaging for that line. But, you have to have the password.