Perhaps you should try some spelling variations:
tang hanh » tang thanh, dang hanh, nang hanh
chay tren » thai tren, ca tren, cau tren
chau tre » chau tho, cho tre, cau tra
hanh tai » thanh tai, hang tai, han tai
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
cam duc » cam xuc, pham duc, nam duoc
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
cao duc » dao duc, cao suc, giao duc

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 nang xa hoi. hieu ve ((cam duc) OR (cao duc)) tang hanh tai ((chau tre) or (chay tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu ve ((cam duc) OR (cao duc)) tang hanh tai ((chau tre) OR (chay tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu ve ((cam duc) OR (cao duc)) tang hanh tai ((chau tre) or (chay tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu ve ((cam duc) OR (cao duc)) tang hanh tai ((chau tre) or (chay tren))*.