|I had the same problem. cheaper bras from cheaper stores don't cut it. Sometimes you need to throw down a little more money to buy better bras for yourself. Try on lots, there will be a couple you see that give you better looking cleavage than others. In some cities their are actually lingerie stores where people will assist you in finding your perfect bra. Lots of plastic surgeons recommend getting new bras to many women who want surgery on their breasts. Sometimes thats just the simpler solution.
Hope this helps and good luck!