Perhaps you should try some spelling variations:
hinh thai » sinh thai, tinh thai, dinh thi
thuy san » thuat san, thuy anh
hanh tai » thanh tai, hang tai, han tai
cuu tre » cua tre, cau tren, cau treo
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
tu sac » tu sach, tu cac, tu san
nang o » nang co, nang ho, nang ro
ve cac » va cac, vien cac
o lai » o lao

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