Perhaps you should try some spelling variations:
truc ngan » tu ngan, thu ngan, tri ngan
cau tren » cu tren, dau tren, cau treo
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, ang xa, dang xay
mang xa » lang xa, mang may, dang xay
hieu ve » hieu va, hieu van
hang vi » hang va, hanh vi, hang di
ca tren » cu tren, la tren, co tren
ve cau » ke cau, va cau, ve cac

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