Perhaps you should try some spelling variations:
chay tren » thai tren, ca tren, cau tren
ban hang » ngan hang
hieu va » lieu va, hieu qua
cac cuc » cac cuoc, cac cua, cac nuoc
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cho tre » cho thue, khoe tre
tu sach » thu sach, su sach, te sach

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 nang xa hoi. hieu va cac cuc ((ban hanh) OR (ban hang)) lam ((cho tre) or (chay tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. hieu va cac cuc ((ban hanh) OR (ban hang)) lam ((cho tre) OR (chay tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. hieu va cac cuc ((ban hanh) OR (ban hang)) lam ((cho tre) or (chay tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. hieu va cac cuc ((ban hanh) OR (ban hang)) lam ((cho tre) or (chay tren))*.