Perhaps you should try some spelling variations:
sach tham » sach nha
gian cua » gian xu, ban cua
nam thuc » nam thuoc, am thuc, nam thu
hieu van » hieu va, thien van, lieu va
lang xa » lang ha, dang xay, lang van
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
va cua » va chua, via cua, ca 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) or (sach tham)) lang xa hoi. hieu van nam thuc va danh ((va cua) or (gian cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ty) OR (sach tham)) lang xa hoi. hieu van nam thuc va danh ((va cua) OR (gian cua)) tre.
• Adding a wildcard symbol may retrieve word variants: toc ((sach ty) or (sach tham)) lang xa hoi. hieu van nam thuc va danh ((va cua) or (gian cua)) tre*.