Perhaps you should try some spelling variations:
sach nay » sach hay, sach vay, sach nang
nay lang » nam lang, tay lang, nhan lang
cac truc » cau truc, cac tru, cac trung
te sach » toc sach
lang ha » long ha
hieu va » lieu va
truc va » thuc va, thuc vat, trung va
va hang » van hang, va nang, va lang
hang vi » hang va, hanh vi, hang di
ha hoi » hoa hoi, ha noi, xa hoi
vi cua » vai cua, di cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach nay lang ha hoi. ((hieu va) OR (hieu qua)) cac truc va hang vi cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach nay lang ha hoi. ((hieu va) OR (hieu qua)) cac truc va hang vi cua te".
• Adding a wildcard symbol may retrieve word variants: te sach nay lang ha hoi. ((hieu va) OR (hieu qua)) cac truc va hang vi cua te*.