One thing you might consider is that it is possible that a combination of different solutes, which are all individually soluble, can lead to precipitation if the solubility of one or more of the solutes is affected by the presence of the other solutes.

If changes in temperature will enable your solutes to remain stable, and not react, then this is a possible resolution. Another might be investigating a co-solvent or mixture of solvents which might lead to improved solubility.

To enhance the solubility of solutes in a supersaturated solution, there are several techniques you can try. One approach is to increase the temperature of the solution, as this can often improve solubility. However, it is important to note that heating should be done cautiously and with careful monitoring, as some compounds may become unstable or degrade at high temperatures.

Another technique is to use mechanical means such as vortexing or stirring to help dissolve the solutes. This can help break up any clumps or aggregates and increase the surface area for the solutes to interact with the solvent. However, it is important not to over stir the solution, as this can introduce air bubbles and lead to further cloudiness.

In addition to temperature and mechanical agitation, adjusting the pH of the solution can also affect solubility. However, as you mentioned in your question, adjusting the pH from 3 to 7 did not lead to a clear solution. This suggests that the solubility issue may not be solely related to pH.

You can see that a combination of techniques such as heating, vortexing, and pH adjustment may help improve solubility, but it is important to carefully monitor the solution and proceed with caution to avoid any unintended consequences. If the solubility issue persists, it may be necessary to consider alternative solvents or chemical modifications to the solutes to improve their solubility.