Do you mean parallel, or side-chain compression? If you can side-chain the bass so that it "ducks" when the djembe plays, you will get better clarity for each of them.
Also try and 'give' frequencies to each instrument: (I haven't heard the source so don't automatically use these numbers - just an example);
Maybe the bass has 50-60hz, the djembe has 80-100Hz, the bass has 150Hz, the djembe has 2Khz, the bass has 1.5Khz - you cut the frequencies from one source to 'give space' for the other one.
Masking is one of the key things to be able to hear. If one instrument sounds great, *until* you add a second one, that's masking. Work out why it doesn't sound good, and EQ the offending source (NOT IN SOLO), while listening to the effect it has on the 'wanted' source. This is why 'pro' mixers use a lot less EQ (... beware of generalisations of course!) than amateurs.