Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
dang xay » dang van, van xay
luc ngan » luc nganh, luc nhan, luat ngan
hang vi » hang va, hanh vi, hang di
cau luc » cau truc, cau phuc
hieu ve » hieu va, hieu van
sach ty » sach tu, sach thu, xach tay
lang xa » lang ha, lang van
ve cau » ke cau, va cau, ve cac
vi cau » va cau, di cau, viet cau

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