Perhaps you should try some spelling variations:
hanh tue » hanh tu, hanh tuyen, hanh theo
vat hanh » vat thanh, van hanh, va hanh
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
tue cua » te cua
cuu tac » cuu dac, cuu cac, cuu xac
sach ty » sach y, sach tu, sach thu
lang xa » lang ha, dang xay, lang van
xang xa » mang xa, ang xa, dang xay
cua te » cua tu

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 (lang xa)) hoi. hieu van ((cuu thuc) or (cuu tac)) vat hanh tue cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((xang xa) OR (lang xa)) hoi. hieu van ((cuu thuc) OR (cuu tac)) vat hanh tue cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((xang xa) OR (lang xa)) hoi. hieu van ((cuu thuc) or (cuu tac)) vat hanh tue cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((xang xa) OR (lang xa)) hoi. hieu van ((cuu thuc) or (cuu tac)) vat hanh tue cua te*.