Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
van cam » van nam, van lam, van cau
xuc van » duc van, luc van, vuc van
hai cua » thai cua, hoi cua, lai cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((nang xa) or (lang xa)) hoi. hieu van cam xuc van hanh ((dai cua) or (hai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang xa) OR (lang xa)) hoi. hieu van cam xuc van hanh ((dai cua) OR (hai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang xa) or (lang xa)) hoi. hieu van cam xuc van hanh ((dai cua) or (hai cua)) tre*.