Google's making some big improvements to its "Shopping" feature, in an effort to win online shoppers from rival Amazon.

The search giant is letting manufacturers add to more images, videos and descriptions to shopping search results and ads.

While Google is still far from being an online retailer like Amazon, the update should help drive purchases of the 500 million products from 150,000 advertisers participating at any given time, according to Christian Santiago, Google's strategic partner development lead.

The feature, first announced in summer of 2015, aims to tame the duplicate and incomplete search results that often come along with data that comes directly from retailers, who each have their own product numbers and language, Santiago said.

"We have heard from some brands, frankly, that they want to improve how their ads are in the Google ecosystem," Santiago said in a panel at CES in Las Vegas. "We'd rather get information directly from you. What's amazing is that so many manufacturers are depending on third-party retailers." 

Though Google is known for online search technology, shopping has been weak, and shrinking: 55 percent of U.S. consumers now start their shopping searches on Amazon, up from 44 percent the prior year, according to a BloomReach survey of 2,000 U.S. consumers over Labor Day weekend. Only 28 percent of respondents said they begin their product search with search engines like Google, down from 34 percent in the year-ago period. Retailers also saw their share of search shrink in 2016.

Capturing more of the growing pool of online shoppers could be a huge opportunity for Google, said Lloyd Wood, who leads enterprise sales at market research firm GfK, a partner of Google.

GfK data shows that 22 percent of returns are because the product received appears different that what was listed online.

The Google Manufacturer Center opened for self-sign up on Tuesday. Google's "shopping" results will now favor manufacturer information if it is available. And if Amazon decides to participate, it will be treated just like any other retailer, Santiago said. 

"[Manufacturer Center] really tells a better story," Santiago said. "Fundamentally, I think a lot of this has to do with our desire to not only improve the shopping experience by also deliver a more structured, search-like experience."