Perhaps you should try some spelling variations:
nhung cau » chung cu, nhung bai, nhu cau
su triet » su viet, su tien, ve triet
hang cau » hang dau, hang ca, nang cao
van hanh » van thanh, ban hanh, van anh
ve chat » va chat, van chat
hanh va » hang va, hanh vi
loc van » luoc van, hoc van, lo van
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
va cham » va chat, va tham

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 ty ((hang cau) OR (nhung cau)) hoi. hieu ((va cham) or (ve chat)) loc van hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((hang cau) OR (nhung cau)) hoi. hieu ((va cham) OR (ve chat)) loc van hanh va su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((hang cau) OR (nhung cau)) hoi. hieu ((va cham) or (ve chat)) loc van hanh va su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((hang cau) OR (nhung cau)) hoi. hieu ((va cham) or (ve chat)) loc van hanh va su triet*.