Perhaps you should try some spelling variations:
thanh dan » thanh san, thanh van, thanh dat
thuc dan » thuc hanh, hoc dan, thuc vat
dan cua » dan ca, ban cua, dai cua
thuc va » thuc vat, thuc day
tu sach » thu sach, su sach, te sach
tang ma » mang may, tang van
y tang » ky tang, 6 tang, 7 tang
he nam » ha nam, nghe nam
ve nam » va nam, le nam, te nam
cua tu » cua tuc, cua su, cua cu

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 y tang ma hoa. hieu ((ve nam) or (he nam)) ((thuc dan) or (thuc va)) thanh dan cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y tang ma hoa. hieu ((ve nam) OR (he nam)) ((thuc dan) OR (thuc va)) thanh dan cua tu.
• Adding a wildcard symbol may retrieve word variants: tu sach y tang ma hoa. hieu ((ve nam) or (he nam)) ((thuc dan) or (thuc va)) thanh dan cua tu*.