Perhaps you should try some spelling variations:
dang xay » dang van, van xay
toc sach » hoc sach, doc sach, thuoc sach
hanh tri » thanh tri, hanh tai, hanh trinh
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, lang van
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
va nam » ha nam, va nay
cua tu » cua tuc, cua su, cua cu

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 ky ((lang xa) or (dang xay)) hoi. lieu ((va nam) OR (van nam)) thuc va hanh tri cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((lang xa) OR (dang xay)) hoi. lieu ((va nam) OR (van nam)) thuc va hanh tri cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((lang xa) or (dang xay)) hoi. lieu ((va nam) OR (van nam)) thuc va hanh tri cua tu".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((lang xa) or (dang xay)) hoi. lieu ((va nam) OR (van nam)) thuc va hanh tri cua tu*.