Please do NOT use olbas or vapour rub or any similar stuff. It does nothing whatsoever to solve any dominance issues between them - piggy either get on or they don't in the end!
Are your girls having real tussles or are you seeing lots of the classic signs of dominance behaviour like rumblestrutting (rumbling and bum wiggling), mounting, head butting, chinning, chasing off etc. Subadult sows can be quite hormonal, but unlike with boars it very rarely ends up in bloody fights that demand a separation.
What you can do if it is just dominance behaviour: make sure that each girl has a hidey and bowl well away from each other, so the top sow cannot become possessive about it. Preferably have hideys with two exits so the undersow cannot be trapped. Just a towel draped over a corner can consititute a hidey. Like with boys, give them space.
Claire has already given you the link to sow behaviour.