Maybe , there is no sure answer to that, its all depend on how bad it is.
if you drop a bong onto a concert floor, and broken it into millions tiny pieces.
might as well get mob and clean it up, there is no god well choice to get it repair or fix. but on the other hand, if you have piece that there is a small cracks or tiny area is broken off, then we can guide you to fix it.
there is a couple thing you need before the repair processes. preferably with some sort knowledge with glass blowing,
first thing, Safety First, you will need heat resist gloves, goggles, heat resist protect work apron, then you need the tools. high temp torch, and torch stands, and work table. you can setup it in your garage or backyard, I would high suggest not set it up in your house or next tome something flammable . , its not very safe for beginners,
Ok now , Changing the temperature of an object causes stresses in the material as it expands. The outside will heat first and expand while the inside remains cooler and smaller. The difference in expansion causes stress in the part. The faster you change the temperature the higher the stresses. Increasing the temperature slowly will keep the inside temperature very close to the outside temperature. This gives you the best chance of not having the crack expand and break the object.
so overall is just slowly heating up the part where it cracks,until the line disappear,
if you want to put two small piece together, its work the same, heat up to the point it close to liquify, and push them together, sometime if there is tube shape glass, you will have to reblow it, make sure the end it not too hot when you reblow it, and always be extra cautions, blow glass is not easy job to do .
anyway it is no guarantee just the best chance.depend on how solid the hand and how good the equipment you have.
also there is another cheap way to fix it.
there is hard glue that can glue about everything, metal glass or wood, you have just try it all, see which one work the best.