Perhaps you should try some spelling variations:
tan hanh » tan thanh, tang hanh, toan hanh
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
qua cac » cua cac
cac duc » cac du, cao duc, cac dac
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) OR (sac ky)) nang xa hoi. hieu qua cac duc tan hanh ((vai cua) OR (hai cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) OR (sac ky)) nang xa hoi. hieu qua cac duc tan hanh ((vai cua) OR (hai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) OR (sac ky)) nang xa hoi. hieu qua cac duc tan hanh ((vai cua) OR (hai cua)) tre*.