Perhaps you should try some spelling variations:
thinh tai » chinh tai, trinh tai, thanh tai
nam thuc » nam thuoc, am thuc, nam thu
hang tai » hang va, dung tai
hinh tai » chinh tai, hinh thai, hinh bai
lieu nha » lieu khoa, lieu phap, lieu tham
thuc day » thuc dan, thuc vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
lieu ha » lieu va, liem ha, lieu ma
tai hoi » tai khoi, dai hoi, tai hai
ky hang » ky nang, ly hang, ky dang
cua tre » cua te, cuu tre, cua triet

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 ky hang tai hoi. ((lieu ha) OR (lieu nha)) nam thuc day ((hinh tai) or (thinh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky hang tai hoi. ((lieu ha) OR (lieu nha)) nam thuc day ((hinh tai) OR (thinh tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky hang tai hoi. ((lieu ha) OR (lieu nha)) nam thuc day ((hinh tai) or (thinh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky hang tai hoi. ((lieu ha) OR (lieu nha)) nam thuc day ((hinh tai) or (thinh tai)) cua tre*.