Judgements / Liens

I live in Texas and I am trying to buy a piece of property from a guy who has told me that he and his wife both have IRS judgements against them. The county records where the property is do not show any liens or judgements against him or the property I am trying to buy. He lives in a different county than the property I am trying to buy is and I do see judgement/liens against property he has in that county. My question is if I buy the property from him can those judgement/liens in another county effect my buying/owning the property from him? The property isn’t worth much and isn’t worth having a Title co. do the research. He bought the property 7 years ago at a Tax sale and I am sure he has clear title to it.
I guess I really do not understand how judgements/liens work. Seems to me that a lien would have to be filed against the specific property and the judgement would have to be filed in the county where the property actually is before they could have any legal claims to the property…

Thanks in advance!