When bids for keywords or product groups are increased they take a while to affect performance. Keeping this in mind we added the 'Last 7 days changes' option to the bidding optimizations.
This option is selected by default so the system doesn't show suggestions for which bid changes were made (through Optmyzr) in the last 7 days. This prevents you from increasing bids for the same keywords or product groups on consecutive days.
For example, if you filter suggestions by low conversions and increase bids, then the same suggestions may show up again the next day and you'll increase bids again even though they haven't had a chance to perform with the new bid.
However, if you would like to see all suggestions, uncheck the 'Hide 7 days changes' box at the top of the optimization page.