Perhaps you should try some spelling variations:
luc ngan » luc nganh, luc nhan, luat ngan
hang vi » hang va, hanh vi, hang di
sach ty » sach tu, sach thu, xach tay
ca tren » cau tren, cu tren, la tren
xang xa » lang xa, mang xa, ang xa
ve cac » va cac, vien cac
ve cau » ke cau, va cau, le cau
vi ca » vit ca, li ca, va ca

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) or (sach y)) xang xa hoi. hieu ((ve cau) OR (ve cac)) luc ngan hang vi ca tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) xang xa hoi. hieu ((ve cau) OR (ve cac)) luc ngan hang vi ca tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach y)) xang xa hoi. hieu ((ve cau) OR (ve cac)) luc ngan hang vi ca tren".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach y)) xang xa hoi. hieu ((ve cau) OR (ve cac)) luc ngan hang vi ca tren*.