The seller has to deliver clear title to you. One of the duties is to deliver a title commitment outlining the inclusions and exclusions of the title coverage. Here is a link to a good explanation of how to read a title commitment: https://www.ltgc.com/files/technicalbulletins_customers/TipsForReadingTitleCommitment_Jul08.pdf
It is from a particular title co - but the process is the same with all title co's. Pay special attention to the exclusions on your policy. If you have a survey then quite a few of the exclusions can be removed (that is a good thing). You might want to have an attorney review your title for you because the title insurance policy is based on the title commitment. You can get an attorney to review it for a small fee.
Your lender will review the title commitment to make sure it conforms to their standards. But remember this, your lender is looking out for them and not for you. That is the reason I suggest having someone that is workng on your behalf to review the title. The sellers' title co is supposed to be an independant third party, but the reality is this: they have the seller as a client, not the buyer.