Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cac truc » cau truc, cac tru, cac trung
dang xay » dang van, van xay
lang xa » lang ha, lang van
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
truc va » thuc va, thuc vat, trung va
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty ((dang xay) or (lang xa)) hoi. hieu va cac truc va danh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty ((dang xay) OR (lang xa)) hoi. hieu va cac truc va danh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: thu sach ty ((dang xay) or (lang xa)) hoi. hieu va cac truc va danh vi ((cua tre) or (cuu tre))*.