After a hiatus, Google ( GOOG) shares seem to have their groove back. The search giant's stock is trading near new highs and is up about 12% since the company announced second-quarter earnings in July. And the shares are up almost 25% since August lows, which followed a rare profit miss because of aggressive hiring, among other reasons. Google's gains follow a period of relative stagnation for the stock. Before the latest run, shares traded at around levels the search giant first saw at the end of 2006. Meanwhile, the buzz over the last quarter has ranged from new video ads it introduced to the prospects of the company getting into the mobile phone business. But it's the company's core search business that has powered gains this quarter. And tweaks that Google made to its ad-displaying algorithm over the quarter have investors expecting that the company may trump its heady expectations. For the third quarter, analysts surveyed by Thomson Financial expect Google to earn $3.78 a share on revenue of $2.95 billion. By almost all measures, Google continued to take market share in search over the quarter. It commanded about 64% of the market as of August, according to research firm Hitwise. And of the 61 billion searches conducted globally in August, about 37 billion of them were conducted by Google, research firm ComScore said.