Perhaps you should try some spelling variations:
hinh thai » sinh thai, tinh thai, dinh thi
hanh thai » nhanh thai, hanh tai, anh thai
cua tre » cuu tre, cua triet, dua tren
qua cac » cua cac
cac duc » cac du, cao duc, cac dac
duc van » duc va, duc tan, duc manh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
nang o » nang co, nang ho, nang ro
cua te » cua tu
o hai » co hai, so hai, o lai

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 nang o hai. hieu qua cac duc van ((hanh thai) or (hinh thai)) ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang o hai. hieu qua cac duc van ((hanh thai) OR (hinh thai)) ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang o hai. hieu qua cac duc van ((hanh thai) or (hinh thai)) ((cua tre) or (cua te))*.