Cleaning records is a difficult problem. Usually people make matters use, by getting cleaning fluid solute like detergents stuck deep in the groove.
The best defense is to never allow a record to get dirty. If you buy one dirty you have a problem. I suspect your sealed problem records are American pressing from the 80s. A lot of reground vinyl was used. The paper label .was not removed and got worked into the vinyl. It looks like dust, but it isn't and there is nothing you can do about it. In that era I would not buy US pressings. I used to purchase from a firm out East that only carried European pressings.
Keeping a record clean means only handling it at the edge and label. Only leave it out while being played. Reurn it to the sleeve promptly and put the sleeve in the jacket sideways, so the record is sealed. Store records vertically under slight pressure.
I use the
Cecil E Watts Dust bug at every playing. They still come up on eBay. That is the only cleaning device that ever really worked.
If you get a fouled record a cleaning machine is really the only answer, but they are really costly.
Keith Monks have made them for years. The Loricraft now owned by SME who now own the rights to the Garrard name is also a good one. Nitti Gritti is an American brand of cleaners.
A fouled record though is a difficult problem with no solution. Don't try that carpenter glue solution.