I enjoy a linoleum floor explicitly 10 years ancient, and....? ...in one place within my utility room there is a 5-6 foot...

...in one place within my utility room there is a 5-6 foot nouns that appears yellowish in color. I've wash and scrubbed it beside all kind of cleaners - even those designed by Armstrong - the manufacturer of my flooring. Nothing get rid of the stain. I wonder if somehow the glue or sticky stuff used to put the floor down is leaking through and cause the stain. Any advise would be appreciated! Thanks.
Answers:    I did flooring for 13 years, and one of the biggest criminal is rugs, especially if they had a rubber finance. Is this a concrete floor, if so there could be something bleeding thru, such as an elder adhesive from previous floors. If this is a wood substrate, could be same problem near adhesives, also some subfloors hold a tendency to produce a stain call tanic acid from tree yap in the wood. In any event when you replace it beside new vinyl form sure you use a new subfloor (birch plywood) my favorite or hold the concrete skimcoated with a cementbased flooring patch. or better but go next to tile, by far most durable and would stand up to flooding.
Bet you had a rug in that, some rugs do that to vinyl,or the sun shines on that spot, so your choice is to put a rug there to cover it or replace the flooring. I vote replace it. 10 years behind the times! You deserve a change.