Perhaps you should try some spelling variations:
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
sac ky » cac ky, sai ky
va dat » va dao, va dau, va dap
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 ky) or (sac ky)) nang xa hoi. hieu va dat nuoc ((van hanh) OR (ban hanh)) dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang xa hoi. hieu va dat nuoc ((van hanh) OR (ban hanh)) dai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang xa hoi. hieu va dat nuoc ((van hanh) OR (ban hanh)) dai cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang xa hoi. hieu va dat nuoc ((van hanh) OR (ban hanh)) dai cua te*.