Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thai cua » than cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
xa sinh » va sinh, xuan sinh, hoa sinh
xa hinh » da hinh, xa tinh, xa vinh
cam tuc » cam xuc, cam tu, nam thuc
van cam » van nam, van lam, van cau
mang xa » lang xa, mang may, dang xay
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((mang xa) or (nang x)) hoi. hieu van cam tuc ((xa hinh) OR (xa sinh)) thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((mang xa) OR (nang x)) hoi. hieu van cam tuc ((xa hinh) OR (xa sinh)) thai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((mang xa) or (nang x)) hoi. hieu van cam tuc ((xa hinh) OR (xa sinh)) thai cua tre*".