Use the Jump to ID option available in the quick search feature to locate the test case or test suite you are searching for.
For example, if you have a requirement tracker artifact with the association entry: "CTF888_TL888:44:artf1118 - TS1", type "CTF888_TL888:44" as the Jump to ID unique identifier. You will be navigated to the corresponding test suite page in TestLink. Similarly to search for a test case "TL888-1", type "CTF888_TL888-1" in the Jump to ID search box and the corresponding test case is displayed on the TestLink page.