Perhaps you should try some spelling variations:
sach hay » sach han, sach ha, sach vay
sach nay » sach vay, sach nang, sach ngan
va hanh » van hanh, va thanh, va danh
cau luc » cau phuc
hieu ve » hieu va, hieu van
lang ha » long ha
ha hoi » hoa hoi, ha noi, xa hoi
vi cua » vai cua, di cua
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: tu ((sach nay) OR (sach hay)) lang ha hoi. hieu ve ((cau luc) or (cau truc)) va hanh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach nay) OR (sach hay)) lang ha hoi. hieu ve ((cau luc) OR (cau truc)) va hanh vi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach nay) OR (sach hay)) lang ha hoi. hieu ve ((cau luc) or (cau truc)) va hanh vi cua tu".
• Adding a wildcard symbol may retrieve word variants: tu ((sach nay) OR (sach hay)) lang ha hoi. hieu ve ((cau luc) or (cau truc)) va hanh vi cua tu*.