Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
sach ty » sach y, sach tu, sach thu
cam duc » cam xuc, cao duc, pham duc
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
ty nang » ky nang, ty xang, ty hang
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 ve) OR (hieu van)) cam duc va danh vi ((cau tren) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) cam duc va danh vi ((cau tren) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) cam duc va danh vi ((cau tren) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. ((hieu ve) OR (hieu van)) cam duc va danh vi ((cau tren) or (cua viet))*.