Imagine labelling a museum illustration of the body. The Sanskrit term asthi fits fairly comfortably beside the English word bone. Other labels are less tidy. Rasa, for example, can bring to mind taste in a discussion of food, yet has another role in the classical account of bodily constituents.
The seven dhatus are conventionally named rasa, rakta, mamsa, meda, asthi, majja and shukra. A translation might offer fluid, blood, flesh, fat, bone, marrow and reproductive tissue as rough guides. Read them as clues to the passage, not as seven labelled samples from a modern pathology laboratory.
If two books choose different words, note what each author is trying to explain. A glossary for a first-year student may compress a distinction that a historical commentary spends a page unpacking. Keeping the Sanskrit next to the translation allows you to revisit the question without losing your place.
Further reading: Indian perspectives on Ayurveda (NEIAH)