It is not uncommon for an adhesive to be required to ensure that the tissue proteins stay attached to the glass slide during staining and other handling. Several have been recommended, but none are suitable for all purposes.
It has been noted many times that a clean, grease free slide will almost always allow for adhesion of tissue proteins when heated for long enough. The time is temperature dependent, but 30 minutes with the wax actually melted at 60°C is usually adequate. Before searching for an adhesive for problem sections, ensure that your slides are clean and grease free, i.e. water wets the slide when dropped on it rather than beading, and be careful to handle slides only by the edges. If slides need to be cleaned, separate them and soak in iso-propanol overnight, then dry and polish with a soft, lint free cloth. This may solve the problem.
A personal observation is that some brands of slides which are provided by the manufacturer wrapped in plastic film have two very sticky slides included – those in contact with the plastic at either end. Sections adhere on touch and can’t be removed for repositioning, nor during staining. These two slides can be collected and used when greater than normal adhesion is required. The slides used were from Germany.