Perhaps you should try some spelling variations:
trung gay » trong gay, trung tam, trung cap
thien van » thi van
lam trung » lam truong, nam trung, lam trong
gay tinh » may tinh, tay tinh, giao tinh
hieu van » lieu va, hieu ve
tu sach » thu sach, su sach, te sach
tinh vi » trinh vi, tinh voi, tinh va
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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 van) OR (hieu va))) or (thien van)) lam trung gay tinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. ((((hieu van) OR (hieu va))) OR (thien van)) lam trung gay tinh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. ((((hieu van) OR (hieu va))) or (thien van)) lam trung gay tinh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. ((((hieu van) OR (hieu va))) or (thien van)) lam trung gay tinh vi cua tre*.