When Google (NASDAQ:GOOG) reported earnings, everything looked well, at least on the surface. Revenue growth was 19%, paid clicks were up, and the company generated significant free cash flow. However, there are at least three things that investors may have missed if they just read the headlines.

Google's site is getting worse
If you were to ask people what Google does, most would likely say it's a search company. Google dominates the search landscape, and the company routinely reports on paid clicks and cost per click.

In the current quarter, the company's paid clicks increased by 26%, however the cost per click was down 9%. This mimicked the company's numbers last quarter, when paid clicks increased 31%, but cost per click was down 11%. What investors can take away from this is, Google has to discount its cost per click to drive paid click growth.

By comparison, Yahoo!'s search business showed a different tactic. Yahoo! reported paid clicks increased by 6%, however the cost per click was up 8%. Since Bing powers Yahoo! search, it's also worth noting that Bing's advertising revenue increased 38% in Microsoft's (NASDAQ:MSFT) current quarter.

The first challenge facing Google is the company's search business is likely to continue its slowing growth. According to recent research, search advertising is expected to grow by about 13% annually over the next few years, as display advertising is expected to grow by 16% and social networking advertising may grow by as much as 30% per year.

The bottom line is, Google appears to be propping up its paid click growth by discounting its costs. Research suggests this trend won't be reversed soon, which should mean Google's revenue growth will continue to slow.

This business is playing with Google's results
In looking at Google and its competitors' fastest-growing businesses, investors need to question what will happen with Google Play going forward. In the current quarter, Google's "other" business posted revenue of nearly $1.6 billion, and this represents the second challenge facing Google. The company's "other" business results represented a sequential decline from the nearly $1.7 billion the division generated last quarter.

In addition, Google's other division's growth rate slowed significantly. Last quarter, this division grew revenue by 99% annually, but this rate dropped to a 50% annual increase in the current quarter.

By comparison, Microsoft's fastest-growing businesses are the company's Office 365 business, which grew 100% on the commercial side, while the Azure business increased revenue by 150%. Yahoo! doesn't split out its Flickr or Tumblr businesses, but it seems clear these are the future of the company.

What's ironic is, Google gets a lot of press from its "other" businesses like Google Fiber, Google Play, Google Glass, and more, and while these businesses are growing on a year-over-year basis, a sequential slowdown is something investors may have missed.

Better than its peers, but slowing down
The third issue investors may have missed from Google's latest earnings report is the slowdown in the company's operating cash flow growth. In the prior quarter, Google increased its core operating cash flow (net income + depreciation) by 17% on an annual basis.

In the current quarter, this operating cash flow increased by roughly 10%. Though this 10% increase is a better result than the 18% operating cash flow decline by Yahoo!, or the nearly 3% decline at Microsoft, it still represents a 40% slowdown.

Final thoughts
In the final analysis, Google's search business is slowing down. The company is propping up its search growth with discounts, but this can't last forever. Its newest businesses declined sequentially, and its growth rate was cut nearly in half.

Last, but not least, Google's core operating cash flow still grew by 10%, but this represented a 40% slowdown from the prior quarter. The stock has been a stellar performer, but if these three issues continue, the stock's best days may be behind it.