If you give insufficient informations you can't expect satisfactory answers. You should be more specific. For exemple, if your solid is thermally stable, you can try sublimation. If your mixture contains isolated particles of each species, you can try sedimentation. Or you can try flotation. And maybe your compound is not insoluble, but only little soluble. So you can try extraction. And why you don't want to use DMSO?

I apologize for the little information, but I can only predict theoretically my compounds' properties. So, theoretically it must be soluble to non-polar solvents, but I tried a few, as well as combinations with more polar ones and it doesn't work. Maybe it requires large volumes, but that doesn't help me if I wish to purify it through column chromatography. I don't want to use DMSO, because it is difficult to remove any trace of it later.

I excuse you for not revealing details because your type of research is highly competitive. My answer is based on the limited data you are giving:

I understand that you have solid mixture of several components & among them is the targeted compound. You want to apply solid-liquid extraction (leaching) but the problem is only DMSO (slightly volatile) works.

I suggest that you try chlorinated hydrocarbons such as chloroform or dichloromethane(DCM). These are highly volatile & are widely used in extraction.

Thank you for the suggestions, I'll try them and see what happens.