Perhaps you should try some spelling variations:
luc nganh » chuc nganh, luat nganh, luc canh
dau tren » dau tien, dat tren, dau tieng
luc ngan » luc nhan, luat ngan, vu ngan
sach ty » sach y, sach tu, sach thu
hang vi » hang va, hanh vi, hang di
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
sach uu » sach luu, sach tu, sach xu
vi dau » vi dai, va dau, bi dau
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) or (sach uu)) lang xa hoi. hieu ve cam ((luc nganh) OR (luc ngan)) hang vi dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach uu)) lang xa hoi. hieu ve cam ((luc nganh) OR (luc ngan)) hang vi dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) or (sach uu)) lang xa hoi. hieu ve cam ((luc nganh) OR (luc ngan)) hang vi dau tren".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach uu)) lang xa hoi. hieu ve cam ((luc nganh) OR (luc ngan)) hang vi dau tren*.