Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
hieu van » thien van, lieu va, hieu ve
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cam cuc » cam xuc, cham cuu, pham cuc
cuc ban » cua ban, cac ban, cuu ban
cua tre » cuu tre, cua triet, dua tren
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 tru nang xa hoi. ((hieu van) OR (hieu va)) cam cuc ban hanh vi ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tru nang xa hoi. ((hieu van) OR (hieu va)) cam cuc ban hanh vi ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tru nang xa hoi. ((hieu van) OR (hieu va)) cam cuc ban hanh vi ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu sach tru nang xa hoi. ((hieu van) OR (hieu va)) cam cuc ban hanh vi ((cua tre) or (cua te))*.