Brace yourselves, gang. "Search for My Tongue" is about…a search…for the speaker's tongue. So we're done here, right?
Well, not exactly. It's worth exploring the way that the title includes the poem's central metaphor, which is namely the use of a tongue to represent language. This is actually a special kind of metaphor called metonymy, and it shows us how the speaker is doing more than just having trouble negotiating a second language. She's figuratively looking for a part of herself.
In this way, the poem's title announces that our speaker is on a quest. She's a searcher. Only, she's not looking for a city of gold or ancient artifact; she's looking for a missing part of her identity. Calling a language "my tongue" introduces an immediacy and an intimacy to the speaker's problem, and that notion is carried out throughout the poem. This is much more than a language barrier. It's an identity problem, and this poem's choice of title lets us know that right away.